Maybe he is the one who doesn't want her to meet any more straight, white men who seem interested in her.
If you really want to meet her you could tell him you're bisexual, attracted to him, and have considered your get-togethers with him dates. (I am borrowing part of a Roseanne episode here.)
Maybe you were too aggressive about meeting her and he was protecting her as she and he don't need to deal with needy male friends. Sounds harsh to say this but some unattached males expect too much. Your friendship is with him so enjoy it.
Gandhi: Happiness is when what you think, what you say and what you do are in harmony .
“I came from a real tough neighborhood. I put my hand in some cement and felt another hand." -- Rodney Dangerfield