I'm still in love with my first boyfriend,he's with someone else,how do i cope?

he stopped talking to me less than 2 months ago. so i haven't called him or text him or anything. i been going out,and having fun.my friend took some photos of me and this guy when we went out and posted one of me and the guy onto facebook.the next day my exes friend tagged him in a photo with another girl. they looked cosy.anyway i'm not coping very well. i want to get over it,but i am finding it difficult.he was my first boyfriend and its really hard to see him with someone else.