I always feel that way too, unwelcome. I'm always embarrassed to try to join in. It's a false belief though because at a party everyone is mixing. Do you ever talk about philosophical things? That's good for conversations getting deeper. Just a single remark or observation can get a conversation going deeper. It may fail a few times but keep thinking along those lines and you'll draw in people with the same types of thoughts.

Keeping superficial that only draws in more superficiality.