His Father

I'm very miserable this morning because my b/f and I got into a fight last night. Everything is ok now (well at least it seems to be) but its still bothering me so I figured I would get some advice on here. First of all, my b/f is Cuban so he speaks spanish. Which is not a big deal to me, he speaks english really well, although he speaks spanish to his father/friends. Which like I said, isn't really the problem b/c if it was, I could take a spanish class. Anyways, my b/f is always inviting his father everywhere we go. Before we started dating him and his father used to spend all their time together because he was the only family that he had over here. Plus his dad is all alone in his apartment and my b/f has been living with me now for almost a year. So my b/f feels like its his responsibility to see his dad and give him company whenever he can. Which I totally understand, I think its great the relationship he has with his dad. Not many kids have that. But all the time?? I mean every time we want to go somewhere he invites his dad. Well, I shouldn't say everytime because we do go out alone sometimes and I see him everyday alone b/c we live together. But still, he doesn't ask me first and I end up feeling like the third wheel because he ignores me and they speak spanish (which doesn't really matter). Anyways, Saturday we are supposed to go and spend our whole day at the fair. I've been looking forward to going with my b/f because I always wanted to go with a b/f and last year I got to do that but it was with a different guy and a really bad experience. Plus my b/f just started college and has a job so I haven't really seen him lately. So I was really looking forward to spending the day with him at the fair!! I have been since last week! Last night he calls his dad and when he gets off he says he invited his dad to go. Without asking me first. So I was quiet about it at first and then I brought it up and told him how I felt. Well, he didn't really say anything and when he did he said that I know how he feels about this and that he has to spend time with his dad and he thought I wouldn't mind. Well, we have already talked about marriage and I love him more then anything and want to spend the rest of my life with him. So I want to work stuff like this out. But he said, "What are you going to do when my mom comes over? If you feel this way now then you'll always feel this way. You'll feel like the third wheel all the time." I told him things can be worked out because I want to be with him forever. But he almost seemed like he thought if I couldn't deal with this then we should break up, he didn't say it, but I got the feeling he wanted to. I said something to him about this and he said no, not at all. He just wanted to know how I felt because this is how it is going to be. I'm just so upset, it ended with me telling him that he needs to tell me before hand so we can talk about it first. But he was like, ok, he isn't going and I said yes he is. Because I want my b/f to be happy, I don't want to make him miserable over this b/c he is really stressed right now. Anyways, I don't know what to do!! I don't want this to ruin our relationship. Like I said before, I love him and I want to be with him forever. But I think this really needs to be solved so both of us can be happy. I don't want to fight about this again!!! So any suggestions/comments would really help. Thanks a lot. Sorry this is so long!!