How do i tell my bf that i am depressed?

Well it's sometimes hard to talk about mental health with people closest to you because you never know their reaction to it, you should talk to him and say that you are feeling depressed and let him know that it's not his fault (unless it might have something to do with what he did) tell him you might need some time or that you're trying your best and that it wont affect your relationship of course unless you choose to let it.

p.s. I'm happy for you that you're telling him because it's always better to have someone by your side rather than to feel alone❤I hope it gets better for you

honestly that's a hard toipic to talk about but if yall have one on one  conversations alot and you feel as if you can trust him.. you should start off with  "alot has been on my mind" or "alot  is going on with me" and if he seems intersted  in what  youare  saying should tell him. if you cant go to someone  you can talk to for help.