How to deal with sexual frustration in a young relationship?

I (22M) am having trouble trying to cope with my frustration. My (22F) gf isn't very active on the bedroom, I know that after 3 years on a relationship things are bound to cool down but this is seriously affecting me, in the first year it was 1 time a week and now is 1 time a month (on good months), we both are going through rough times on our lives and currently she is having a lot of trouble in her moms house.

We already had so many conversations about this subject but the conclusion is always the same: she feels pressured when I try to seduce her, and if I don't make the first move then we don't do anything. Sometimes I just don't feel enough for her, maybe I am too ugly or just not attractive, but other people find me attractive so this confuses me.

The frustration is eating me from the inside and the possible solutions end up making the initial problem worse, when I try to exercise my libido grows exponentially, working more or studying more makes me stressed (which makes me want to decompress by having sex) and I have been volunteering for charity every now and then but when I come home and see her it just comes down to the same thing.

When we end up having intercourse we have a great time, I usually make her cum twice so the issue here isn't my performance. Sorry for derailing a bit, also sorry for the bad english. I just wanted to vent and seek advice on how to cope with the lack of desire from my partners side, I know this isn't goint to change and I'll have to adapt to keep my relationship with her, and I love her so so so much.