Please re read your "question". If your best friend wrote that, what would you tell her?
Sweetie, you are being used for sex. Yes, you are. Every single word of your question points to the fact that you are this guy's sex kitten. He has no interest in you other than to have sex with you. He found himself a girl who is so desperate to keep him that she puts up with a "relationship" based on sex in a car, dressed up as a sex kitten. Wow. Are you an adult? Because are acting like an immature child.
Your initial words are "I want more than he can give me". There is your answer right there. He cannot give you more, not because he can't, but because he WILL NOT. Why should he? He has this sex on demand chick any time he asks.
You are being so fooled and so used by this guy. He will not leave his current living situation to be with you. He will never take you out in public because that will jeopardize his living situation with his girl friend. And, yes, she is his girlfriend. They sleep together and yes, they have sex.
He lied to you about everything so you would have sex with him. When he found you he hit the jack pot because here is a girl that will dress up in lingerie and have sex with him in a car and put up with being used. You are so easy to lie to and you are every man's dream to have this sex on demand chick who has no self respect.
Think about that the next time you put on sex clothes to meet him for car sex.
This is a question from a troll, isn't it. No girl can be so stupid, or can she?