Maybe she is not very social or she is just shy?
Maybe you should try to hang out with more couples because she is shy?
I have noticed since I am in a long term relationship hanging out with other couples is the norm now lol. It just feels different hanging out with single people with my gf there.
Sex problem?
Maybe you need to spice it up a bit and introduce new things like new positions?
Embrace her more instead of shutting her down all the time?
Since your the man you have to sacrifice more than her in a relationship if you want it to continue.
Pretty much fuck what you want and like because its going to be all about her.
OR FUCK ALL THAT
introduce her to some drugs lol then she would like to party more