what’s wrong with me 😞

Okay guys so lately I’ve been really depressed. 
It comes in waves like large waves. I was in a depression stage for about 6 months then I was extremely happy for almost a year and now I’ve been sad a lot lately. (These waves have been going on since I was probably 15, now 21) 
Last year I found love for the gym and went from 185 to 149 and I was happy I lived in a nice apartment and was single. 
My apartments lease went up in July of 2017 and moved back in with my dad to save up and for the past 6 months I’ve been trying to get a apartment with my best friend but due to some financial situations with her we’ve had to put it off a little. 
Around July/August of 2017 I started getting serious with a close friend who I now call my boyfriend we’ve been through a lot in the past nine months as a couple and during these nine months we would argue a lot and my confidence went straight down the drain, I quit eating to only once a day practically starving myself but still almost gained all my weight back. 
He broke up with my last month and I felt free I felt like maybe I could turn myself around. Quit smoking weed, get back in the gym etc etc. 
Well he is coming to a realization that he needs me and that he loves me and he deeply regrets breaking up with me. I explained to him how I want to turn my life around and be the happy fit girl I used to be and he claims that he wants to help me too and let us grow as a couple but I just don’t know. He seems genuine and I believe him but I feel like he is the reason why I can’t shake this sadness and depression. 
My boyfriend suggests that it’s not his fault and that I need a counselor. 
Please help .