Desperate need of Advice - Chronic Worms in Cats

Little bit of background information. 

Two cats, one male, one female. Male is roughly 10 years old and the female 6 to 8 years old.

We adopted the male first, he had no fleas, no worms, very healthy cat. Approx 5 months later we brought home Remi (Female cat.) We adopted her from Petco. Her paper work claimed that she had be given a flea bath, and deworming medications. She was checked by a Vet and given a clean bill of health. Besides being incredibly afraid of us for the first few months she seemed to be perfectly healthy. Took her a while to warm up to us. About 2 or 3 months after we got her we noticed these little rice looking things around her tail. Took her to the vet, they said she had worms and gave us medication for worms and tape worm. We gave it to both cats. This was almost 4 years ago.

No matter what, like clock work, about a month after we take her to the vet and give her the medication (on time, both doses) she will get worms again. We do not have fleas, they are both treated for fleas anyways and I have never once seen a flea on either of them. We buy a new litter box, we bleach their "area".. We give them a flea bath, we do everything in our power to try to help her get rid of them. The cats are INDOOR only. Never allowed outside.

4 years later and hundreds of dollars spent, she STILL has worms. We just did another round of worm treatment not even a month ago and tonight I found a worm on her anus area. I'm getting desperate. We have a two year old child and I refuse to allow the cats to run freely in the house while they have worms. We keep them separated from rest of the house until something can be done but we have done this over, and over and over again. They are older cats and I fear giving them away, they would put Remi to sleep. She doesn't like change what so ever and growls at strangers. She's a one home cat and probably couldn't handle a change but what can we do?? We can't keep spending money every month like this to keep taking them to the vet. The only thing our vet does is give us more medications and tell us to treat the house for fleas. We have!! MANY times! I'm going INSANE.

Please. If we don't get this figured out, I'm done. I can't take it anymore and I will get rid of them. I don't want to do this and have avoided it for 4 years... This is the last straw.

Sorry it's taken so long for anyone to reply.

First off, has your Vet identified the type of worms these are?  Have they specifically said "tape worm"?  Those are the type of worms that cats get from fleas. 

Next, what medication are they giving you to give the cats, and what dosing instructions are they giving you?   Deworming usually requires multiple dosing to get rid of both the adult worms and the larvae, and the timing has to be just right before the larvae hatch and make new larvae .

Once we have these answers, hopefully we can help you out.  We don't want you to even think about having to give up your furkids! (but I realize this can be extremely frustrating, especially with a small child at home )

Yes, ask the vet for another dose to be given 2-3 weeks after the first. The eggs hatch, the new worms grow up, etc. To be absolutely certain, maybe ask for a 3rd dose too.

If the vet visits are just too much, Tapeworm Tabs will work fine and you can get them at most pet stores.

And something to get rid of the fleas. The most effective meds on the market are from the vet (Nexguard and Bravecto), but Advantage or Frontline may work for you.

You can perhaps try  Diacetomeus Earth,, DE.  Just make sure its Food grade.   Works both internally and externally.   Although with externally put on the fur, there is some danger of the cats breathing it in.