You have a hunch that your girlfriend wants to break up with you.
It's causing you so much pain and confusion that it's driving you mad.
You desperately want to fix the problems, but you really don't know what to do.
The problem is getting worse by the day, and you need help immediately.
If you call your girlfriend, does she still answer your calls with as much enthusiasm as before, or does she let the phone ring for a while before answering? When you are talking to her on the phone, is she still as bubbly as she used to be, and excited to hear from you, or do you talk and she replies with a yes or no answer? When you suggest going out somewhere, even to her usual favorite place, is she thrilled to go and accepts right away, or does she give every excuse under the sun as to why she can't go? Then you say that, instead of going out, maybe it would be great to spend a quiet evening at home - before you've even finished speaking she tells you she has a headache.
My friend, these are all clear signs your girlfriend wants to break up with you.
Something is really irritating her so much, that she is becoming resentful of you and the relationship, and is gearing things up to break up with you.
My suggestion is to leave her alone for a while - give her time to sort out her feelings and make a decision on her own.
Your girlfriend wants to break up with you - all the signs are there - and this could go either way.
If you leave her alone for a while, she might begin to miss you or, she might grab the opportunity and end the relationship while she has the chance.
If the latter happens, then accept it with dignity, get over it as soon as you can, and get on with your own life.