Brother returning in a few days I am dreading fully?

I know everyone has sibling rivalry and you eventually grown out of it, I feel like we'll never grown out of it. He's 23 and I'm 21, he is so cruel to me and not in a joking way. He is good academically and has a great social life. Girls swarm him like flies on honey, I have had only 1 bf. My brother calls me ugly in (he's completely serious) and tells me no guys want to date me, my dad supports his point cause my brother has the young guy perspective and he's like well he knows what he is talking about. My social life is ok a few friends just hanging out and stuff nothing like my brother though. My brother says I don't have social skills and I act immature (this is a person who was trying to put boogers on his gf in a cafe). I don't talk much cause I don't know his friends and I don't know how I act immature he says I get sit or stand too close to people, like I'm almost sitting on their laps. Ya I will sit next to someone on the couch but I stay as far away from them as I can. He goes out of his way to be cruel and even mocked me with another friend of his (also college age), they also almost made another friend cry that night. When I get really upset my parents step in and tell me that I need to calm down. I try to ignore him but he like follows me and really gets on my nerves. I suffer from a low self esteem and feel like crap about myself, but he doesn't care. What do I do? (I can't avoid him cause my family is close).