Question for all Mommys that have a stepchild! My boyfriend has a daughter I consider her my own…

Question for all Mommys that have a stepchild! My boyfriend has a daughter I consider her my own because because I love her like my own but lately I've been having a huge problem. Anytime my boyfriend and I are laying/sitting next to each other she will get in the very little space between us and lay right beside him pushing me off of him or as soon as I get up to do something I come back and she's laying/sitting exactly where I was leaving no room for me. If he gives me a hug/kiss and she sees she will hurry her way over and to get a hug/kiss. I can understand maybe a little jealousy but lately it's really been bothering me I feel like we can't show any affection towards each other because of the way she acts 😕