Not sure if friendship is worth it?

Hi All,

I need some on my friendship with my best friend Dan. We have been friends for 12 years but lately I feel like we aren't close anymore. I find that whenever we hang out he just talks about his life and gossips about other people. I am going through a tough time right now (my aunt was diagnosed with cancer) and he doesn't seem to understand how difficult it is for me. The other day when I told him that she may not survive and he just said "aw" and then started talking about college applications. I'm not even asking for his sympathy, I just want someone to talk to about it. Now whenever he asks to hang out I always say no and can't explain why. I guess I feel like everything we used to talk about is so petty and immature. I'm not mad at him, I just think that i'm out growing him. I have ignored his texts and calls for the past couple of days because I don't know what to say to him. What do you guys think I should do? I'm not sure if our friendship is even worth it anymore.