I'm going to read my ex's chats.
Are you going to read your ex's chats because he is being a jerk? What do you think you'll gain from it?
It really hurts when you break up with someone to find out he's happy without you.
Breaking up can bring lots of emotions, but you shouldn't read your ex's chats in any circumstance. Move on and leave old relationships in the past.
I can't help wanting to know who he's chatting with.
Letting go of old relationships can be really hard but reading your ex's chats is an invasion of privacy. Also, obsessing about them isn't healthy, you have to put some distance between the two of you.