SUBREDDIT: r/relationships
TITLE: My girlfriend [23F] of 2ish years flip flops between being very physically interested in me [25M] and not being interested.
POST: My girlfriend and I have been dating for a bit over 2 years and we have lived together for about a year. In general things are very good: we get along, have fun together, rarely argue and resolve disputes well. 

However, the one major issue that we have is that I'm a very physical person; I like lots of kissing, cuddling, sexing etc. My girlfriend, on the other hand, alternates how physical she likes to be quite a bit. Some weeks she feels the same as me, but then will go for chunks of time where she just doesn't want to be touched at all. 

We've talked about this and she says she is attracted to me and that it's not personal, but has to do with the mood she is in at the time. She (admittedly) is a pretty moody person. So, these times where she doesn't want physical contact can be pretty frustrating for both of us because I want to touch her or initiate sex, and she just wants to be left alone. She has tried to be more affectionate during those moody times, but when she does she ends up feeling resentful. This is especially frustrating for me. 

We are not sure how to solve this issue. My feelings are hurt and I often feel frustrated. Obviously, we are very happy in other areas and breaking up is not something we are considering. Any advice on how to overcome this disconnect in the amount of physicality in our relationship would be helpful.
TL;DR: 
girlfriend goes through moody periods where she doesn't want to be touched and it is frustrating for me as a very physical/affectionate person. What to do?