I cannot choose between two guys, help?

I have been with my boyfriend for a year and a half. We have our share of problems.We have both cheated, broken up, and hooked up with others while apart mutiple times. Every time we would forgive each other and get back together. Due to school, athletics, work, and other arragments we have not been able to see eachother much thus creating small problems with trust because we both tend to wander when we lack attention from one another. Recently I met a new guy. He use to be a huge player but has settled down (or so he says) who is a sweetheart to me. Every time the new guy and I go out he pays, compliments me, and tries to make me as happy as possible. He is very kind to me and loves spending time with me and giving me attention. It worrys me that he will wander because of his nature and I will be cheated on. A few days ago I learned that my boyfriend has been flirting and joking around about hooking up with another girl via facebook and I guess he flirts with her at school (he is in highschool and I am in college). I love my boyfriend but his flirty and outgoing personality makes me question if he can remain faithful to me, especially since he will be staying on campus next year and he will be 3 hours away from me. My boyfriend has been amazing to me while we have been together, other than the cheating, yet trust is lacking. This new guy also has the trust issue because of his past. What are your comments or opinions?