Eh, all of her boyfriends treated her badly at some point. But the last time we see each of her boyfriends, I would say:
1) Jess was the best. He got her back to Yale, didn't he? He was so hurt when she said she loved Logan. 
2) Logan was second. He was obviously in love with her, but I thought the ultimatum, all-or-nothing deal was weird and harsh.
3) Dean was last. The way he talked to Luke was repulsive.
But all IMO, of course. 