"Seeing how this cycle happens again and again, I am not sure: am I just being too picky and stressing out about pointless things, or are these real concerns that I should be aware of"

Well .. I was going to say that you two have already been in a relationship for 4 years now. And it seems like you know a lot about her. But here's the thing: shouldn't you love your girlfriend for who she is? Sorry to say this, but if you really dislike her so much or are complaining about her so much, maybe she isn't the right one
That's just my opinion.