??

Stop discussing him with your friend, for a start, even if you're lying to her.

Anything you say to her may be passed on, and not necessarily accurately. Any relationship (of any kind), she will see as her property.

Now, on to him ...

First, make up your mind what you want, and be honest. You keep telling her you don't like him, but you obviously do (or you wouldn't be here). At least be honest with yourself.

"might've unintentionally gave him the cold shoulder". Unintentionally? I know attention-seeking, passive aggressive behaviour at 100 metres. Unless your are 12 years old (or under), don't you think that's a little sad?

And finally, he has a girlfriend. So back off. How would you like it if someone muscled in on your boyfriend?

And what would you think of a guy who hadn't got the guts to end it with his girlfriend, but was already lining up the next one, using her gullible friend as a go-between?

Relationships cannot exist without respect. You aren't even being honest with yourself, so there's a self respect issue; he's deceiving his girlfriend plus he's coming at you via a friend, not face-to-face. So he doesn't respect you or his girlfriend, does he?

If you want a jerk who will treat you exactly as badly as he treats his current girlfriend, go for it.

And, sadly, you will.