How to tell him!

My boyfriend is aware of my eating disorder but I don't think he understands I'm having the feelings of relapsing again.. don't know how to tell him. I've lost a total of 40 pounds since last June. I keep losing more and more. Today one of my guy friends said I can tell you don't eat because look at yourself... it triggered me in a way I've never expirenced it was the words I've always loved hearing even my moms friends comment on how much weight I've lost... my mom and dad hate that I can lose 10 pounds within two weeks but they can't lost 5 within 2 months. They don't think I need treatment but the feelings are coming back strong! Help please!