What can I do?

So I've liked this guy for 3 years and I befriended him for a bit until I did something so stupid. I went on my sisters account and said all this stuff too him. My sis found out and hated me and the guy told me everything too my sister but not me.

I told him the truth and he blocked me on facebook and I told my sister all though she was mad she got over it awhile.

And now the guy keeps giving me like I don't the cold shoulder. He always looks at me and smiles but never talks too me. Now he has a girlfriend who I hate and I don't know if I should forget him or move on and also he has moved schools and I never said goodbye.

What can I do?