Depression over actions

I cant seem to shake off or let go of the past and has been creeping into my life everyday.
I plays over and over and makes me so angry and depressed about the issue that occurred.
My therapist says you cant let it bother you and consume youre life all of the time. Its easy for him to say that if he doesnt have the issue that I do.

I swear I beat myself up emotionally because i feel i dont deserve to be happy with myself because I hurt my friends and family too much. Its a constant battle with my spouce over the littlest things that get me going. I dont know how to handle or fuction correctly sometimes and it gets the best of me always.I want the pain to go away.The drugs and the medication seem to not fix the problem. I think it makes it worse because I am a different personality than i was before I had my meltdown.

I want to end this crap going on in my head so bad and just have some relief in my life so I can be happy with myself once more and not feel so depressed and suicidal at times.