The invasion could have come from anywhere.

Maybe the wash-and-fold laundry down the street. Maybe the lockers at the 92nd Street Y, where I swam in September during my pool’s annual closing. Maybe a bag in the cargo hold on the plane I flew home from Europe this summer. (I’m sure it wasn’t the two private homes where I stayed.) Maybe a sleeve I brushed against on the subway, or something that stuck to the bottom of my shoe. Maybe another apartment in my building.

However it happened, bedbugs have taken possession of my life, and shredded it.

Saturday night a week ago, I was feeling fidgety and having a hard time sleeping. About 2 a.m. I turned on the light to read. A bug ran across the sheet. I pulled it up to find more. In all, I killed about two dozen that night, pressing their bodies into the blue-and-white shell-pattered sheets, leaving trails of blood — mine. I have not slept in my bed since.

In the 2011 film ”Contagion,” a microorganism dropped onto a leaf in the jungle by an infected monkey eventually makes its way to the United States via Gwyneth Paltrow, who dies of it, and brings the world to the point of apocalypse. That’s pretty much what’s happening in New York City, where the inescapable proximity of 8.3 million people makes it easy to pass bugs or their eggs from one to another to another. One bedbug can lay up to 500 eggs in its lifetime, the Internet tells me, so if you carry home even one egg, you can expect 500 bugs and their descendants.

Trying to pinpoint the source of the infestation, I asked experts how long it would take for an intruder to make its presence felt. “Don’t even go there,” more than one told me. “You can drive yourself crazy.”

I notified my landlord, whom I already owe more money than there is in the world, and he contacted Abalon Exterminating, whose motto is “We do it all!” Someone from Abalon called to schedule an appointment for last Wednesday. A few days, and my problem would be solved.

On Wednesday morning, I walked the five blocks to the Bug Off Pest Control Center in Washington Heights, which had been recommended to me, to buy casings for my mattress, box spring and pillows ($138). I was visibly upset when I walked in. As the owner, Andy Linares, looked for the casings, he displayed all the finesse of his previous career as a United Nations diplomat.

“What did you do to bring them in?”

“Nothing!”

“Have you been picking up furniture off the street?”

“No! Look, just give me the cases.”

“Hey, I’m trying to help you. It’s not about the money.”

No, it’s about blaming the victim. Bug off, indeed.

When I unexpectedly had to leave home by 5:30, I called Abalon to ask if the exterminator would be finished by then. Of course: “he’s only doing an inspection today. He has to determine if you have bedbugs.” Apparently my bloody sheets weren’t good enough. But then, to Abalon, bedbugs are an everyday occurrence, not a life crisis.

Then I was e-mailed the instructions for preparing my bedroom for extermination if it was found to have bugs:

Clothing and any other items stored under the bed must be removed washed and bagged

Clothing stored in dressers and all other storage areas must be removed washed and bagged

All clothing, linen and any other items in closets must be removed, (at last, a comma!) washed and bagged, all closets must be completely empty

Radiator covers must be removed for access

Smoke alarm, electric outlets and switches must be removed

Furniture must be removed from the wall at least 24 inches for proper access (this in an 8-by-10 room)

Carpet needs to be lifted along with padding and tackles, are rugs must to (sic) be washed

Window treatments must be removed, bagged and washed, all hardware must be removed

All other items listed must be vacuumed before treatment and then sealed in plastic bags

That’s days of work.

It’s times like these when a single women finds out how entirely alone she is in the world. An impossible list of tasks, and there is no one to help. The few friends you trust enough to tell may sympathize, when they’re not making jokes, but nobody shows up. “Could your brothers help?” one asked. My brothers are pushing 80 and live two states away.

Wednesday’s mail included my lease renewal — another increase in an already unaffordable rent. My “rent-stabilized” apartment has gone up $500 a month over eight years. Bedbugs included.

That same day, I was informed that the reason I’ve lost so much weight and look so great — size 8 jeans! — is that I have thyroid disease, possibly cancer. I am a freelancer in the United States of America; you can imagine how much health insurance I have.

But we should count our blessings. A nice young man did arrive mid-afternoon to do the inspection. He lifted my mattress. A bug ran across the box spring. “You have ’em,” he said. Inspection completed.

Even with paid help from my housekeeper and her husband — thank you, Irene and Ricardo — it was going to take at least a day to do the required preparation, so I asked for an appointment Friday. Abalon was very busy that day but granted me an 8 p.m. appointment, after which I would have to be out of the apartment for four to six hours, pushing bedtime to around 3 a.m. on the night before a very long day. I was very tempted to book a five-star hotel room for the night, but Priceline couldn’t supply one for the $100 I was willing to spend. As it turned out, the money would have been wasted.

I completed the preparation as instructed. More than 20 black trash bags now take up the available floor space in my living room and work area. I sleep on the springy mattress of the living room foldout, with no comforter to pad it or sheets, for fear of harboring bugs. The legal heating season has yet to begin, so I’m sleeping cold, which means poorly.

On Friday night, 8 o’clock came and went, with no sign of an exterminator or explanation why. I called Abalon; they called the exterminator, who called me to say he had been looking for a parking place for 45 minutes. Sometime after 9, I called Abalon again to reschedule. “How about tomorrow morning?” Megan asked. “I can have someone there at 7.”

7 a.m. Right.

“How about 10? I have to leave by 12.”

“I’ll have a man on your doorstep 15 minutes early.”

No one showed up, at 9:45, at 10 or after. By 11:30 I had screamed at several receptionists. Finally the manager on call for the weekend phoned me from his car en route upstate for the holiday weekend, promising an exterminator at 10 the next morning. He even gave me a name, Eddie Verso, but refused to give me Eddie’s cellphone number. I went to the theater and seethed.

Eddie was due at 10 a.m. Sunday. At 10:26 I was about to phone the manager when another call beeped in — Eddie, who was doing a treatment at a hospital in the Bronx. (It took me a few minutes to realize that he was doing a treatment — killing bugs — rather than having one. “Treatment” is a euphemism for spraying.) He would be here between 12 and 1, he said. I went out for brunch with a good, stiff bloody mary.

He arrived at 12:56. He came, he saw, he sprayed. He even did some tasks I hadn’t asked him to do, like filling the outlets with diatomaceous earth. Eddie is the hero of this story, one of the very few people who have taken the situation seriously. Thank you, Eddie.

I had to be out of the apartment for four hours after the spraying. To fill the first two, I went swimming. The rest of the time I spent sitting in my lobby, my laptop running on battery, writing this post and quite possibly picking up more bugs. I had actual conversations with two of my neighbors, both named Mark. “Oh, yeah, we had bedbugs, three, four years ago,” said Mark from across the hall.

And that is my life from now on.

The person who’s been the most helpful is the one I expected to be the least: Charlotte, mother of Julia and Skunk, the two wonderful cats I have been babysitting while their home undergoes major renovation. I fully expected Charlotte to whisk them out of my life forever the minute she heard the word “bedbug.” Instead, she picked them up in brand-new carriers, left two giant bags of food, took the girls off to a kennel and, inexplicably, returned them just minutes ago. I have been counting on Julia to warm my sofa bed and Skunk to make me laugh. The two of them have spent three days behind bars for a crime they did not commit. I hope they will come to trust me again.

Eddie may have killed the bugs, but their effects won’t be going away. Every itch or tickle makes me feel under my clothes for a bug. Every speck of dirt I see has to be pressed to see if it leaves a trail of blood. The doctor said I might be feeling a bit manic because my thyroid is in overdrive. He doesn’t know the half of it.

Bedbugs have cost me days of my life and, so far, hundreds of dollars — in bedding replaced, help hired, laundry and dry cleaning yet to be done, lessons canceled, freelance work I’ve had no time to do. The book I’m allegedly writing? Fuhgeddaboudit, as New Yorkers say. I publish this post fully realizing that it may cost me badly needed employment. Would you want someone who might be carrying bedbug eggs ushering patrons to the red velvet seats in your theater? Any more than you’d want her sleeping in your spare room, or sitting at your dinner table?

I’ll be living in squalor for two more weeks, until the follow-up spraying and the cleanup afterwards. I’ll have Irene vacuum the bedroom while I take out the mounds of laundry. When I feel it’s safe, I’ll put a new comforter on the bed, and maybe then I can get some sleep, though I’m not sure I’ll ever feel truly comfortable in this apartment again.

Cancer will just have to wait.