Welcome to the boards, seakapper.
I'm going to toss a few different things at you, just to get started, and then we can talk more as you'd like and take it from there. I do have some questions it'd be helpful for you to answer so we can get a better sense of what might be going on and help you out as best we can.
What your doctor says: because a medication doesn't have an impact on something at one time doesn't mean it isn't at another, or won't later. So, if your doctor is suggesting some of this might have to do with the antidepressant you're using, and is suggesting you try a different one, I'd, personally, go ahead and do that. As your prescribing physician, your doctor's advice (unless you have concerns they aren't competent) is the central advice to go with when it comes to medications and their impacts. And indeed, some antidepressants do have this impact, and there are some which are known to have less of one. Why not try something different and see?
On saying you feel "numb down there": Are you saying that you're not just no longer experiencing orgasm, but also aren't experiencing pleasure? In other words, when you masturbate now, are you actually feeling a real desire to? Are you feeling turned on at any point? Does touching yourself still feel good and satisfying?
Too, you say this change started for you -- alone, I'll get to the different issues with partners in a sec -- around three years ago. Were there any other changes for you around that time, like changes to your health, where you're at when it comes to menopause, changes in your life as a whole, changes with your body image or your own joy in your sexuality?
Per what you're talking about with partners: The bigger issue with faking orgasm here really isn't about honesty, but about doing something that all but assures you won't stand a chance reaching orgasm with a partner. Think about it like this: if we tell people, year after year, person after person, that we like our eggs soft-boiled when, in fact, we don't like them that way at all, all we're ever going to get are soft-boiled eggs, rather than our eggs how we like them. Faking orgasm gives who we are faking it with information that says what we are doing together works for us.
On the other hand, when we're honest about what does and doesn't work for us, then we and partners can actually learn what DOES work, what IS satisfying, and what we DO like, so that we can get all of that, either right away, or in time.
You're almost 60 years old. Getting through sixty years of life on this earth as a woman in the world is one helluva haul. Getting through all of that and still being concerned with satisfying men strikes me as a pretty sad situation: the least you have earned in all those years is the right to focus on YOUR satisfaction, and to stop worrying about satisfying men, don't you think? They're grownups, just like you are. They have the capacity to take care of themselves. And if what they are earnestly satisfied by IS you experiencing pleasure and reaching orgasm, then you share a goal and a want. But to reach it, for both of you, you've got to be real and honest, otherwise all any of you are getting is a sham.
I'm going to say this again, loud, to you just as one older person who has lived through this life a long time as a woman to another:
FORGET WHAT SATISFIES MEN. YOU DESERVE TO FOCUS ON WHAT SATISFIES YOU.
Too, if you keep picking partners who you feel you have to fake it with, and who accept a fake, and don't have any real desire to take the time with you to explore sex together and discover what you both enjoy, then no kidding you're unlikely to have satisfying sexual experiences with partners. So, some of this may be about who you are choosing here as well as the dynamic you're setting up by faking. Catch my drift?
Viagra, for the record, doesn't actually increase desire or make orgasm more likely. All it does is increase circulation to make erection happen. So, even if there were something like that you could take, it still wouldn't solve the problems you've been having.