How can i change my password?

ok, I have an AIM account, and i want to change my password.

I tried the "forgot my password' button many times, and when i get to the part where i type in my new password, after i type it in, it says its unscure, and sometimes it says that i have part of my screen name in it, which i do, but its completley different. is there a way that i can change it without having to not have part of my screen name? and how can i change it? I use the same password for everything, and i have the same name for some, and it lets me have the password, and i dont feel like changing every password i use because of AIM...how can i do this?