This is common. Some people respond to grief a lot better than others. If you think like this long enough, and you're prone to it, it leads to depression and anxiety as it eats away at your self-image, and from your description you've got it bad. I've been there several times in my life, as my romantic life wasn't very lucky until I got married when I was around 50. Had many loves, and lost them all up to then. Some of us are just plain unlucky. But how we respond to that depends probably on the personality we're born with and whether we're prone to mental illness. In your case, you appear to be having several difficult things going on at once, and that's even harder. Also, taking a lot of antifungals and antibiotics very often leads to chronic illnesses, as it destroys the good organisms that protect you from harm as well as the ones you don't want. Taking antacids for too long causes the stomach to have to produce more and more acid, as you can't digest protein and some minerals without an acidic stomach. So it goes. I would suggest you look into seeing a psychologist and working on it. I'd also try to stop fortunetelling about how happy your ex is. You really don't know what's going on inside his head. All you know is you didn't want the relationship to end and he apparently did, and that hurts. How much or how long it hurts is more up to you than you are aware of, but folks like you and I were just born not being good at handling that. Perhaps therapy will help you learn to move past this, although no matter what you do, time will take care of most of it and you will meet someone else. Peace.
Anxiety/Stress definitely hard on one's physical health.
If interested research the Sympathetic Nervous System vs. the Parasympathetic Nervous System.
SNS is the "Rest, Digest, Restore" mode. But when we're being chased by a tiger, the body switches into it's "Fight or Flight or Freeze" response, and says "Forget about healing myself we're putting all our energy into surviving the next moment".
Which is great if we're actually being chased by a tiger. Otherwise it's disastrous in today's modern society where we have no tigers, but we can endlessly worry ourselves sick about other possibilities.
So part of healing ourselves is trying to switch ourselves out of PNS mode back into SNS mode, even if just briefly, by trying meditation, or a meditative motion exercise such as qi-gong or certain types of therapeutic yoga.
They're not instant cures, but over time they can help.
(There are numerous meditation apps one can try. Also 'Headspace' has some good short animated videos explaining the concept.)
(Or support groups I personally like. Nice to be with people who understand our struggles and accept us as we are.)
Geminiii, yes. I think that depression and anxiety can take a toll on our body. In essence, your health anxiety makes you feel every little this or that, blip on the radar that most people would just be like no big deal and hardly notice. You escalate it and are hyper sensitive and aware. I'd say, working on treatment of the anxiety is the best bet. I'm glad you are in therapy. BUT, that's expensive and going more than once or at most twice a week is excessive in my opinion. :>) What can your therapist help you with outside of seeing them? What about go to things you can do when you see the signs that your anxiety is about to go off? What about medication? Have you considered that aspect? You are spending a lot of time and money on testing and worry. This is impacting you negatively. I would get very aggressive about treating it. There are apps, calm and headspace. I've tried calm and my son has used headspace. They really aid in meditation which is something I could never master before.