My best friend started developing feelings for this girl back in March. A few of our friends and I decided that we were going to try to help him get with her. 

At first he was excited and really wanted to get with her, and I was happy to help him. But for 6 months straight he was constantly talking about her, with no action. Now, I get it, he liked her and he was nervous to talk to her, but for 6 months straight, every topic in a conversation turned into a talk about her, and I couldn't just tell him to not think about her. One of the most frustrating parts was when he kept repeating himself on what he wanted to do, "I really need to talk to her one on one in person" etc, but he never followed our advice .

Jump ahead to the end of the 6 months and he actually began going out with her. GREAT. I can finally stop talking about how he can get with her. Nope. This was his first relationship (he has also never kissed a girl), and I completely understand why he would be a bit nervous about doing things with her. But being messaged nearly every day hearing about their dates, or how annoyed he was at himself for not going for something, it got to the point where I just ignored his messages for a couple hours because I was sick of talking about it. 

After 2 months they broke up, and he claims that he is over it, when he clearly isn't. Any time I mention a girl he tries to give me advice like he is some guru, "Well when I was with my ex" "Bro honestly from past experience I know that.." , but he barely even held her hand after 2 months. 

He still talks about her to this day and it has gotten to the point that I don't even like hanging out with him anymore, especially when it's just us two, because I know he will just bring her up and I have to say the same routine phrases over and over again, "No you're not in the wrong" "No I understand why you were nervous" "Don't be mad at yourself" etc etc.

TL;DR
AITA for not wanting to hang out with my friend anymore, because he will just talk about his ex girlfriend, who I had to hear about every day for the past 9 months?