*&gt;&gt; I don’t know what to do*

You're 22, life hasn't even begun yet and you're staying with someone who lies and cheats effortlessly to your face?

Leave.

Dump the cheater, go out, meet other people, grow and realize she's NOT the only woman in the universe, even if it seems like it right now through your oxytocin-addicted brain.

Love is a powerful drug and you need to detox right now.

There WILL be other women, better ones, worse ones.

Don't condemn yourself to a life in purgatory, there is only pain, tears and regret there.