I am speaking only from personal experience, but anxiety and IBS symptoms go hand-in-hand for me . . . in the beginning, I would also go for extended periods of time . . . as I began to understand, recognize the causes and triggers, and invest in the recovery process, both anxiety and IBS has become less intense although I am not cured of either . . .
I would recommend that you have a complete physical re: your symptoms to eliminate a physical cause (unless you have already done so) and work with a counselor who specializes in anxiety to help to guide you with management techniques (again, unless you have already done so) . . .
Until you find out whether your symptoms are physical or anxiety-based, you will not know the appropriate road to take but you can recover.
The other thing that I would like to address that your anxiety appears rooted in regrets from past decisions . . . again, speaking from personal experience, you cannot change the past . . . did you do something "bad" to someone? If so, can you rectify it by recognizing what you did to get some closure and then to move on with your recovery and your life? If you are regretting decisions that you made or did not make, learn from it but don't relive it because you will get stuck in the past . . . right now, your future is entrenched in your present and the best that you can do to recover is to start to work on you, preferably with professional intervention . . .
Your bottled up feelings have to get out somehow . . .if not with a professional, then may be in a journal . . . as difficult as this process may seem, as you relieve yourself of your feelings of guilt and regrets or whatever, you will begin to develop a sense of renewal that will keep you going even if you hit speed bumps . . . and always remember, come here and let us know how you are doing . . . as a community, we will support you as best we can . . .take care, kc