Did he really love you?
When you still love the person that broke up with you, you want to get back with them. Regardless of how much of a jerk he has been to you...the way he can treat everyone else nice, and then totally disrespect you. YOU deserve better, much better. You are just comfortable with him, and yes, the comfort is a very nice feeling, but you can do better than him; there is someone out there who will love you, and treat you like he does. Definitely don't try to rush into another relationship just to have someone to cuddle with, and do things that you and your ex did.
Try not to think about him, and i realize that is hard when everything that comes on the radio makes you think of him, and random objects, places and foods. Don't only think of all the happy good times, you need to keep in mind how much of a jerk he is, and how you do Not deserve that.
You need time.
It sure doesn't seem that he has truly loved you, the way that you have loved him.
Cliche, but true...
-Time heals all wounds
-There are other fish in the sea
-Someones trash, is anothers treasure ---not that your trash, YOU're the tresure :)
-The grass isn't always greener on the other side ---he may see that soon, and want to get back with you!
BUT, if he has dumped you before for someone else, then you MUST Move On.
He obviously does not see you, or appreciate you, for who you are. He is taking advantage of your love for him, and just using you as a back up.
Once he sees that you won't be a back-up, that may make him miss you... Be strong.