Most Helpful Guy
I've been that guy before. You don't want to be with that guy. Even if he's honest about his feelings for you he will continue to do this to you, just get out now and get as mentally far away as possible.
Most Helpful Girl
If he loved you he wouldn't have cheated on you for 2 months and ended up in a relationship with another girl , simple as that. Let him go. He sounds immature and not capable of maintaining a relationship