Letting it out

Ex left me almost a month ago, he’s talking to someone else he previously knew. They’ve known each other for 11 years and have never met once. Due to her anxiety or at least that’s what she tells him but I feel like you would meet someone you are into no matter what. I still love him a lot. We live together as we signed a lease 3 months ago. But we do sleep separately. Not in no contact yet. Well the past few days he’s been talking to me very sexually and talking about stuff we use to. Well last night things took a turn and he was tub in my back and things happened. He waned it to happen and was planing on doing it well when we were doing he said we shouldn’t have done that. And proceeded to say this girl told him to do it for closure…. But like who would really tell someone go do it with your ex for closure if you were serious about them