DP and I moved in together recently. She still spends the occasional night (1 or 2 a week) at her mums house which is absolutely fine with me. But she never discusses with me which nights she's going to be staying...she just doesn't bother coming home and leaves me to work it out basically. She thinks this is fine...i think its rude. She's thinks I'm overreacting and picking a fight over nothing...am I?