Sorry to be blunt, but speaking as a man, you're setting off all the alarm bells.
You're in a relationship that you say is unhappy, but you don't leave it. Or at least, not until strangers on the internet tell you to, and then you go for it.
That tells me you don't know your own mind, you don't have appropriate boundaries, and you lack self respect.
You're actively seeking out someone new while in a relationship. That tells me you have the moral compass of an alley cat.
You talk about unrequited love, while simultaneously saying you don't want to respect him (ie it's just sex). Your posts lack self awareness or emotional maturity. That tells me you may be quite emotionally unstable, and may struggle to maintain an adult relationship that isn't built on drama.
If he is in any way a decent man, those are the things that are putting him off. Sorry to be so blunt, but I think you'll struggle to find a decent, mature fellow who would be interested while that is the path that you are following.
My suggestion would be that you have some work to do on yourself. And that you may be better off doing that without the distraction of a relationship with the crush, the existing boyfriend, or anybody else.