Boyfriends Mom

Katie

So my boyfriend and I have been together for 4 years now. I'll be 19 in April and he turned 20 last weekend. So I took last weekend off of work for his birthday, but his mom decided that she didn't want to celebrate last weekend because his sister was in Florida for cheer nationals. So they decided that they would celebrate this weekend, well I told them that because they decided on that after the schedule came out I wouldn't be able to be out at his moms house (45 minute drive) till 4:30. His mom decided that they would celebrate his birthday as a family without me and planned to do his birthday activities right about the time I got off of work. I can't help but feel like it was to intentionally exclude me because the last time I saw his sister she was mad at my boyfriend and left because she wanted to spend time with just her family. Also when we divided Christmas between my family, his dad and his family (his parents are divorced), and his mom she threw a fit and told us that we shouldn't spend the holidays together because she barely got any time with him on "Christmas fricken day" because we weren't going to be there for dinner to celebrate with my family. Any time that he chooses to be with me she guilt trips him. I don't know what to do because I was invited to go out there after all of his birthday activities were over tomorrow, but I honestly don't know if I want to. It feels like I'm intruding every time I go out to his moms house and it just seems like I'm not wanted. This has never been issue before the last couple months. I love my boyfriend more than anything and we have talked about a future. He even expressed to his mom that he wanted to propose (before all of this) and she told him to wait at least two years before proposing. I just don't know what to do or what to think. Do I suck it up and go out to his moms even though I hate it and have to work early the next day? Do I tell him I don't want to go, even though it will really upset him? Any advice on how to deal with his mom and sister if I do go over to their house? Any advice in general? Thanks in advance!