I would stop the medication and working so hard to try to herd a cat :-) I have two 10 year old cats and one of mine is like yours, under the furniture when you most want to get her to the vets or something. I had the at-home vet come but she could only look at the "friendly" one (who I had to hold and he's strong as an ox and was not cooperative; he does not like being constrained); a waste of a lot of money.

It is very depressing; I worry if one of mine gets sick because I can't get them near a carrier/to the vets. My "friendly" one has an extreme fear of water (want him to leave an area, turn on a water faucet) because he had to be sedated to be bathed; I didn't realize that until the damage was done.

I think if you quit "chasing" your cat and leave it alone it might become a little more comfortable and eventually "forgive" you? I would work on that. It is very sad to have these companion animals that run from us rather than enjoy us. My two are fine on their terms; like to be "near" me (my female who was half-wild as a kitten "lets" us pet her but often will settle just a couple inches away from where we can reach and/or attack us if we pet her when she doesn't want to be petted).