Boy problem

So there is this boy in my grade level. Our school splits each grade into 2 classes. He is in the other class as me, and I like him. Like a lot. He said that he likes me also, and now I don’t know what to do. At one point in time we were “dating” but now we are not. He says that he has a cold heart, so it takes a while for him to accept you and stuff. I recently heard that he doesn’t like me because I was in a time where I was pretty sad and stuff, but then he also emailed me and sent stuff about how he was sad and didn’t want to live. I shared my sadness with him and we would email me again and again. I’m not sure what changed in him, but supposedly he doesn’t like me because I’m always sad. Im not sad and I have a lot of fun hanging out with friends in school. He can obviously see me laughing at lunch time and stuff like that. I’m not sure what to do because I still do want to be with him and stuff. Also I’m in 8th grade. 🙃 I would really love you guy’s advice. Love you guys!! 💜