<human>: I will be graduating college next month and will be having a joint graduation party with my cousin who is also graduating. My twin sister has an alcohol problem and eating disorder which caused her to leave college so she will not be graduating like me, which is actually pretty sad seeing that we have always shared everything. I know it shouldn't bother me, but I just want the best for her and hope some day she will have her own graduation. She is dealing with this by constantly making jokes about her 'failure' to finish college whenever talks of my graduation come up. I know it is a defense mechanism. It doesn't annoy me too much at all. Really, I just feel sad that she is sad.

She has been dating this guy since November who I don't think is a good influence, or even a nice guy. He makes her walk to his house (sometimes walk home at 1-2am), never takes her out, she pays for everything. He only comes to the house when my parents are away. When my parents are away he usually sleeps over and last time his car blocked mine in the driveway. I had to get to work so I moved his car and apparently this really annoyed him. Basically he stays over and sleeps till 2, then monopolizes the living room the entire day while my sister and him blatantly ignore me. I really dislike him. I also suspect he smokes weed with my sister.

When my sister is with him, she acts like an annoying teenager you would find in hot topic. No other way to explain it. He won't even come into my house with my parents home, yet my sister thinks he should get invited to my grad party. Seeing that it is my party, I don't think it is crazy for me to say I do not want him there.

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<bot>: Sister's boyfriend won't even come into my house and meet my parents, but sister thinks he should get invited to my grad party. I dislike him. I do not want him there. Am I justified?