My(23F) boyfriend(24) has been suffering from depression for a long time and has had a rough childhood. I've noticed that he has these episodes that last about 3 weeks where he goes from happy, hopeful and content to very depressed and wanting to commit suicide. His therapist told him that he suspects that his depression is only a symptom of a bigger problem specifically BPD.
But from what I've read he doesn't have that many symptoms. He's not controlling or possessive. He's an over achiever, very smart and always plans ahead. He always apologizes for his mistakes and never disrespects me. And these episodes don't sound like Bipolar either as they're not that extreme. Only the depressive episodes are extreme. What could it be?