I really need advice

I dated a boy for three and a half years. He broke up with me a few months ago for a girl at our high school. He would talk about her and I never thought anything about it because I thought he loved me and she isn’t even straight she’s a lesbian and he just doesn’t know this. This isn’t a rumor btw. I know high school is full of rumors but I’ve known this girl and her family for a long time. I feel bad for her though. Her family is very religious and she dates guys so they won’t find out. She even resembles a guy so people say my ex isn’t sure about his sexuality and that’s why he left but idk.

I just wish the memories of us would go away. I feel so stupid for ignoring the fact that he talked about her a lot. He got her number like two weeks before we broke up, I just didn’t know.

I can’t get the fact that I lost my virginity to someone who’d do this to me. I lost my virginity to someone who pressured me into having sex when I didn’t want to. I didn’t do all this for him to leave me. I should’ve seen it coming. I’m naive. I feel like love isn’t even real and I’m too young to have such a serious relationship. I’m a senior in high school. I loved him I really did. Now he is completely gone.

He always told me he was going to marry me. He acted like he loved me when he really didn’t. It was all a lie.

I can’t make the dreams go away. It’s been months and every night I’ll go to sleep and have to be reminded that he doesn’t love me and he loves her. I even see her in my dreams. I see them together. I’ll even see us together. I know it takes time but is there any other way I can make them stop?