Is this depression or do I need to break up with my boyfriend?

It sounds to me like the traumatic experience may have effected you quite a bit. When depression strikes you, it changes absolutely everything. I recently went through this as well. I have been married to the love of my life since September and after 3 months, I suddenly felt the same way you are describing. Although mine went a little further. I would be overly mean to my husband and treat him as though he is a cheating . I was always sad and felt so alone and had no energy or motivation. It was bad. I knew I had no reason to feel this way, and I only wanted to show my husband how much he meant to me and Not push him away. So I went to see my doctor. You said you are on zoloft, and you still have these episodes, you should tell your doctor about it. If you need to, write when you feel this way. Wright down everything you think about, how bad you feel and how upset you get and just everything you feel... when you are under these episodes. It is a good idea. I think you should try it. Maybe you can find something that triggers it, or maybe your doctor can find a different medication for you that would work. I do hope you try the writing thing. It helped me a lot. Good luck and take care.