Well if your taking meds, I would hope you are seeing a therapist about your issues, believe me I have found that when we worry about a spouse or sig. other cheating or leaving us, IT IS OUR OWN issues of cheating or insecurity in self. I would talk to your doctor and work on these issues, as for myself, I believe I have to trust, unless I can put a chip in his head and track him 24/7, but would that be love? or trust?
IF you are putting on a ring for Marriage, Domestic Parnership or Friendship, One must have LOVE & TRUST. when you have this the anxiety has no more power! good luck, Hope you work these issues b4 marriage, why bring unwanted baggage into a marriage.
I can't answer your question about the meds but as for your personal issues I had the same problem with my wife except I was thinking she was cheating on me to the point that I developed some of these anxiety issues. I have since learned that you have to trust your partner and even though you tell yourself you do you have to be able to trust him without thinking about it just like breathing it just has to be there. If you can do that then maybe you can get off some of those meds. Good Luck