He used to hate me but now he says he loves me?

I met him back in eighth grade. He was sitting in the office cause he's a bad kid and I was an office aid cause I'm a good kid. I was instantly drawn to him. I said to myself "I have to meet him" So I found out we had a mutual friend and he introduced us to each other. We started to like each other. I asked him out. We dated for 3 days. I was only 13 then so I was dumb and told him I love him and wanted to marry him so he broke up with me and stopped talking to me and called me a stalker. In ninth grade we became friends but he was so mean to me. He always called me ugly, stalker, slut. He would make fun of me in front of everybody and say he hopes I get hit by a car. He even got me to do his work for him and pay for his lunch everyday. He moved to Texas about 6 months ago. I just added him on facebook and he called me and said he misses me and that my pictures look nice, he even told me he loves me and that he wants me to come visit him. He said when he's 17 in too years he's moving back and wants to marry me and have kids with me. He also said he doesn't want me talking to no other guys. I was so happy. But I don't know, should I trust him? That this is real and it'll last?