Confused about this long term relationship?

Me and my bf lived together 3 yrs. Our relationship was good, we rarely argued, etc. but then I moved out to grad school. This school wasnt a good match for me. Instead of handling my anxiety I got addicted to a computer game. My addition was bad. I got sick, lost 15lb, no interest in a lot of things, being one. I quit the school and moved back in to recover. In 1/2 year my bf moved away for his studies. After a month being apart we talk, I ask him where we're going. He says he is not sure about me, suggests an open relationship, i say err no. Soon after he starts dating several girls and gets a new gf. Then dumps her in a month and says he realized he loves only me, feels bad about what he did. He now says that I have spooked him cuz I was asking about marriage and for him it sounded like i wanted it tomorrow. I am starting grad school 2nd round, so i couldn't have said that. I am confused, I love him but now i have my own doubts. Should i try to work this out or time to move on?