Feeling like an emotional monster

To clarify i have 2 friends and haven't told many people who i really am. I am a monster who causes pain and misery. The last three weeks of my life I've relived everyday of the 29 years of my life. I ruined my relationship with a person who tried to pull me out the dark. She took me in I was broken, knowing my scars and my struggles she tried to give me hope. I watched my brother pass away 5 and half years ago. He committed suicide. I was in the other room I had to see it all. I dont blame him we had horrible childhoods. I used this depression as a crutch and became a evil person. Pushed everyone away from me but the woman who gave me everything but eventually became hostile towards her. I broke her down I put all my pain on her with anger. She left me after 5 years im surprised she put up with me so long, i deserve it. I find myself alone again drowing in a hole of misery i put myself here. I dont know telling strangers will help but its a start. I don't wanna be the person i am anymore. I depressed lonely monster. No need to reply to this not much to say im suffering and its my fault