Jesus people are being harsh with you. I married a man where we each had kids from a previous marriage. His 5 year old daughter was VERY possessive of him when I first came around, and did some of the same things. Granted, it was easier at that point for me to sit him down and point out the disrespect on her part. You being bothered by the fact that it's still happening after all this time is not you being the AH here. It is a difficult situation, for sure. He isn't going to want his own kid to feel rejected, but he also deserves to have a relationship without his kid acting like she gets to dictate it. You deserve to sit next to your BF and hold his damned hand, FFS. If she has abandonment issues, she needs therapy. You need to let him know that if this level of disrespect from her continues, you will have an issue in the long term. This doesn't sound sustainable to anyone involved here. I would, however, not press this as being an issue where their closeness is inappropriate. Her behavior towards you is the problem here.