Try not to feed into your anxieties and wait and see what she says when she comes back home for the weekend. She is still young at just 23 and if you crowd her and get too controlling she will distance. It's just that she is at that age where it's normal to want to be independent, that has nothing to do with you, just her stage of development.

It's a challenge to love someone and try to trust them and give them space. The thing is if she is going to cheat etc., then she will do it regardless and nothing you can do about it. You have to learn patience and given you stress that can be a challenge.