What do you think of me breaking up with my gf after a steady 4 year relationship because she won't kiss me?
Really, why does it matter so much if she won't kiss you?
A good kiss is an important part of any relationship. It's unreasonable for me to stay with somebody who doesn't want to give me a good kiss.
I can understand how frustrating it might be for you. You shouldn't impose demands on how your partner when it comes to their autonomy over their own body. Maybe you should talk to her and ask her what is going on that she doesn't want to kiss you.
It's possible she's just moody and that is why, but I will break up with her anyway.
It might be so, but you are right to break up with her. It is better then to force her to kiss you when she doesn't want to.