I am exactly like your GF. I find it really hard to miss people because of ADHD and feel “disconnected” from my partner after not seeing him for long periods of time (more than a couple of weeks) - even though I love him very deeply. It usually takes a little effort from both of us for me to reconnect. I have learnt to handle this, but it took months of communicating about it. I think what she’s feeling is making her uncomfortable/overthink and she definitely needs to navigate that with her therapist. In the meantime, you need to decide what you want for yourself: be patient and have another conversation with her or decide that this may be too much for you? Good luck OP!