Please help me. Trouble with my sister and now this dream.

[ALIEN]

Hey everyone! I'm new here and I'm really sorry to jump straight to the point but I'm in a little bit of a situation and i would really appreciate your help.

Ok, so in reality, my younger sister (shes 20) has a boyfriend who only and only takes money from her. For this and that and everything. And shes only been with him for a month but he has convinced her that he is in love with her and wants to marry her, telling her "you are the love of my life, the sunshine of my world... blah blah blah... oh, and I need some money for petrol."

You see what my problem is? My sister is completely buying into his nonsense and has had fights with me because of me telling her I dont want to see her boyfriend and I dont want him using my house and car for his needs. She is acting like a child.

I had a dream tonight where:
----- I was having lunch with him and my sister and I was more or less fine with him. But I ordered blueberry pancakes and he kind of became tense and I asked my sister jokingly "what is wrong, did I order too much or something?" and she said yes, them both looking at me like I'm some outcast. Then he ordered bottled water for all of us and I really didn't like that. Im not sure why but it felt like he overstepped some boundary, like i was entitled to order my own choice of drinks and he did his own selfish thing.
So I asked my sister to come outside the diner and talk with me and we had another small argument, but I no longer remember it completely. -----

Anyways, he and my sister are going to my parents house to meet them tomorrow and Im not sure if i should go. I dont want the guy thinking i welcome him into my family. the last time i met him, he got the idea that he could use my shower in my apartment.

Im not sure what to think. Can someone shed some light on my dream and/or situation?

Thanks in advance!