I'm a Cancer female and I hope I can help offer you some insight into a Cancer mind. Doeyedpisces is right- We do like to mess with people. Although, sometimes we really don't know we are doing it. Cancer likes to push the envelope in some social situations.
A Cancer can come off quite easily as a b*h or dk. That's because we know what we like and what we don't like. It takes Cancer a long time to open up. We have a wall up when we first meet people and it takes a lot of time and patience for that wall to come down. We are only protecting our vulnerability. Because of this wall, we come off as indifferent and uncaring/unsympathetic when in reality we care deeply about a lot of things.
When a Cancer decides to be in a relationship, they let you into their world. They are trusting you with 100% of their emotions. In sounds like you guys had a rocky beginning to your relationship. Sending a Cancer harsh texts messages is not the way to go about fixing things. He came back around because Cancer's like to give people second chances. However, don't expect this next time around for him to act the way he did before. Trust is EVERYTHING to us. You have broken his trust which is why he is acting standoffish. It may take him a very long time to get over what happened and decide to trust you again. All you can do in the meantime is keep giving him reasons why he can trust you and it will slowly build back up to where it was before. I do mean SLOWLY build. You have to decide if that's something you want to wait for. Again, there is no guarantee that things will ever be the same.
At this point, as a Cancer, I would say your best bet is that you will be friends with occassional hook ups that serve to satisfy needs as opposed to him desiring you. But, I am a Cancer female...that's what I do. A Cancer male is similar to a Cancer female but I do not know how they are in relationships because I haven't been with a Cancer male.