Please help me. Idk what to do

My ex and I are seniors in high school and we were together almost 2 and half years. Before we started dated we were best friends which made our relationship easy. If there was an issues we talked about it but we only ever had one big fight in our entire relationship.

But two weeks ago, everything flipped. I was rude to him over the phone. I was having family problems and practically tore his head off. Well, he hung up on me and I don't blame him. Sunday morning, I called and apologised for my behavior and he said he was "used to it". I felt awful. I was letting my personal problems hurt our relationship. He was upset so I gave him space. Tuesday at school, he ignores me but would be nice and talkative to everyone else. If I tried to talk, he would ignore me or be bitter. I was trying to be understanding but I was struggling. I knew I had treated him badly but it was fair for him to act that way when I was trying to make things better.

That night he texted me, asking if I would come over so we could talk things out. When I got there, he explained that he was worried that I wouldn't show up and that he wanted to fix things. That night I learned he hadn't been happy "in awhile". I assumed he meant a week or two. I was stressed with family and school around that time. After we talked, he made the first move and we had sex. When I left we were back to being ourselves kissing, hugging, being playful, and saying I love you. He even promised we would go out to dinner soon.

Two days later, he's back to being an asshole to me at school. I was obviously confused because he was fine after we had talked. Friday, he said he didn't know if he had in him to work things out but five minutes later he was being nice again and saying I love you. That night he called me and said that I didn't need to worry, that he loved me and that we would find a way to fix things together. Unfortunately, that weekend we couldn't see each other because of his schedule. Sunday night, I texted him saying "goodnight, I live you" and all he said was "night". I thought it was weird but my mom said he had call her earlier to tell her he was determined to make our relationship work, he was just lost. This made me relax again.

Monday, my mom sat down with us both to help us talk to each other. We asked her to be there to give us advice since we were both unsure of where to go. We had a good talk and once again he seemed okay. The next morning I wake up to a text saying "I feel like we make headway but idk what to do or think". That same day, he went to therapy (he has been for awhile for his depression) and said the therapist made him realize that the relationship was adding more stress to his problem and that it was too much. He said there was nothing I could do and that it wasn't all my fault. He text me this during class and I lost it. I start crying and had to walk out of class because he made it sound like a breakup. At the end of school, we met somewhere to talk. He said he wasn't breaking up with me but felt "boxed in". He didn't want to breakup but he didn't know how to work on things and that he hadn't been happy in two months. This really upset me. In those two months, he had said nothing about being unhappy. We were spending more time together than ever. He even asked if I would live with him after we graduated. The only reason I said no was because he wanted me to live with him and his mom. I was worried she would try to out herself in the middle of our relationship but I did want to live with him. But if he was so unhappy why would he be planning our future?

Wednesday of this week, he ignored me at school. I called after school and he was being nice again. He had to go somewhere but I called him later that night and he said looking at me made him angry but he doesn't know why. I've asked what the problem is and he just keeps saying he doesn't know. Thursday, I decided to ignore him too. I love him but was getting tired of the hot/cold behavior. He still sat with me at lunch and in class, which makes no sense if my presence pisses him off. He could have moved anywhere else but he won't.

Yesterday, was homecoming at my school and he was a king candidate. I asked him if he wanted me there and he said he wasn't going to tell me no. I suggested we go on a break but neither of us believe in them. Basically we ended up splitting somewhat mutually (I mean, what choice did I have?). He said as a person made him happy but a relationship didnt but now that makes no sense. I'm the same person either way. The whole time I was crying and he was hugging me, holding my hand and telling me he loved me. We agreed we didn't want to lose each other. In class, he was acting like we almost did, laughing and joking together. But it wasn't us because I knew I couldn't hug him or say I love you.

The problem is now I've realized that I can't be his friend. Back before we were dating, he was with someone else and I hated it. But at the time I rathered have him as friend than nothing at all. Now I've realized I can't go back. I love him too deeply to be his friend and nothing more. I want to be with him so badly that this is killing me inside right now and I hate it. Yet at the same time I'm mad at him for breaking our number one rule and not talking before we ended up here. I feel used because of all the times we had sex in the last two months. He promised the last two months were real for him too but then how could he be unhappy? My mom noticed he's been partying more and more and thinks that he just didn't want a girlfriend his senior year. That by keeping me as a friend he can do what he wants and come back when/if he feels but I don't know what to think. She thinks he's been playing games for the last (almost) two weeks. All I know is that I want him bad. It sounds stupid but I really do.

As of now, I plan to just stop talking to him altogether. Maybe if he realizes what it's like when I'm gone he'll realize he wants to be with me. But what else can I do??