My ex keeps on texting me about his new girl...Duh? What for?

He is texting me that his new girl havent texted him and he is suspecting that the girl is seing another guy. Heres the scenario, My ex is 32, the girl is 22. They dont have a realationship yet coz the girl is still not ready, ut my ex is so into her already.I just fnd it so irritating that he had to text me about his suspicions and qualms about his new girl. I mean, I said over and over that im not interested. Why is he so insensitive of me. He dumped our 8 year relationship for this young brat, then now he comes to me coz he so damn sad and depressed. I hate it that I have to recieve these insensitive texts from him. I just proved to myself that I dont care about him anymore coz hes so irritating. My question is, why does he comes to me for help and comfort.He said im still his bestfriend. What should I do? Comfort him?