<human>: Can you summarize the given text in a few sentences?

I'm not cheating on my SO, but I have conversations on my phone with my two best friends that I don't want him to read. Some background: He and I broke up in January after two years together because I was severely depressed and wanted to work on things on my own. After months of just hanging out, he and I got back together in the summer. I was wary, but I love him so I decided to just go with it. He doesn't understand that I can't just make myself happy, so I've started acting like I'm happy around him so we won't have to talk about it because it's incredibly frustrating trying to make someone understand depression who has never been sad for very long in his life. I understand that it's hard to wrap your head around because, until this year, I felt the same way. I thought people could just make themselves be happy. 

Back to now: He says that I've been acting funny for the past few weeks. I have convos on my phone with my two best friends about how miserable I am that I didn't want him to see because I really didn't want to talk to him about my constant state of unhappiness. I love him and seeing him happy makes me feel better, but it's somehow not enough and that kills me. So instead of showing him my phone I left and went home. I'm truly disgusted with myself. 

I think my biggest problem is that I don't know whether I want to mend this. He deserves someone he can fully trust and I deserve someone who understands that me being depressed isn't simply cured by thoughts  puppies and unicorns. I do love him... But I don't think I can go back to the exhausting task of keeping up appearances just for the sake of peace.
<bot>: Boyfriend thinks I'm cheating, but I'm actually just severely depressed. Don't know if I want to keep this up anymore.