My boyfriends depression

Hi, please bare with me as I am new today. Here goes.... I met my boyfriend online 3 months ago he was open from the start that he takes Sertraline for his depression, we have only touched on this subject a few times and I can gather he started taking it towards the end of last relationship which he split from in October. Since meeting him we have literally had the best time of our lives in 3 months, and he moved in 3 weeks ago. About 6 weeks he just stopped takings meds because he was in such a happy place and they effected him when we had sex, now I don’t know anything about depression and the mess up until Monday where I have read everything I can. He told me on Saturday via message he was struggling and has been quiet since. I got home on Monday afternoon to a note and he had cleared all his stuff and gone back to his parents, it was a lovely letter but it said he is really struggling with his head and he doesn’t want to be a burden to me. We have messaged each day since Monday but it’s been 24 hours since a reply but he is reading my messages. He can’t stop saying sorry for what a horrible person her is and that he has dragged me into his problems. I don’t know what to do??? His mum is in constant contact with me but he won’t talk to her like he has before, he is just sitting in his room, me and his mum think it’s a good idea I go see him tomorrow. Will that be too much for him? I have read up about just stopping your meds and I know he is going through a crisis because he just stopped but I can’t seem to get him to understand that. He is back at his doctors on Monday which seems a life time away. Any advice is welcome.