I have read the letters on this thread, and I'm impressed with the wisdom here. It really does help to read here!
There are a number of serious issues here, but the one that leaps out at me, related to personal experience, is that the doctor was NOT wise in giving you drugs that conflicted.
She should have at the very least looked those up to see if they fought with one another, or she should have called the heart specialist. I'm told doctors are having to limit time they spend with patients (it is even recorded, the time spent with each one, by a click on your computer record, according to one medical person who confides in me). So this may be one reason she didn't do an adequate job of correlating your meds.

I have gone now for over 16 years without anti-depressants, because I have Porphyria, and sometimes I was in deep depression. But I am glad that I am not burdened with any of those drugs and their potential side effects and interactions. All anti-depressants made me worse off, usually with deeper depression and many other side effects, one of them sending me to the ER with tachycardia (Prozac). I was in the clinical trial for Xanax before I was dx'd with the disease (Porphyria) in which one cannot take anti-depressants.
Xanax was awful. It made me almost unable to walk, semi-paralyzed. I took it two days and gave up. That type of reaction probably wouldn't occur to many here on the MS forum, but it was a big reaction that I thought you might be interested in, since you take it some of the time. For you it may be better than nothing. For me--the WALL. Whatever that means--I guess the WALL means that one must stop an activity no matter what else occurs.