Oh my gosh! I feel horrible, but I feel like I accidentally caused my boyfriend to have a massive depressive episode
Are you serious about this? Why would you do that to your boyfriend?
I don't know what to say, I guess I'm used to seeing people as manipulative.
If a past boyfriend was manipulative I can totally get where you're coming from but you shouldn't let that influence how you see your current boyfriend. You need to talk to him and tell him why you feel the way you do and help him understand. There's a good chance he has no idea why you feel that way and it would help him feel better.
Do you think I should do that for him?
Yes, I really do! Being open with him about what causes you to be suspicious would probably make him feel a lot better. He could be thinking the worst right now about the relationship you two have.