I never post on Reddit, but this has been bothering me so much I need other people’s advice to make sure I’m not crazy or maybe if I am.

So a little backstory, my GF (18) and I (21) have been dating very consistently on and off for about 8 months now. It’s a long distance relationship (I live in England, she lives in the Netherlands). And her ex (18) is still very prevalent in her life as a friend. He got is own place a few months back and she is now consistently “sleeping at his” more often now. It’s not in the same bed, but another bed a few feet away. She swears up and down that she is only loyal to me, but get extremely mad if I ask her to video chat with me while she’s there with him. I trust her but my overthinking gets the best of me. Am I crazy and controlling (from what she tells me) or do I have a decent reason to be concerned that she sleeping with her ex? I can answer any specific questions if anyone has them.

TLDR: GF of LDR sleeps in same room as ex that’s a “friend”, should I be concerned or am I crazy.