Rob, look I've already told you what you need to start doing but you keep saying that you're "afraid to push her away" and that is exactly the crap attitude that will keep you pigeon holed in your current situation for as long as you choose to live like that.
You're afraid to stand up to her.
She knows it. (yes you are, don't bother explaining it, it comes through with the majority of your posts)
FACT: It's not attractive.
Why would she be sexually attracted to you if you're not very masculine?
Here is a test for you and her and yes it will take some balls on your part to actually perform this and unfortunately I'm betting against you, you just don't have it in you and the sad thing is, if it hasn't happened already, you're going to come home one day at the wrong time and walk in on your wife getting pumped something fierce by another man because you weren't man enough to do the job yourself.
Sorry for the description but that's just how it is.
Tonight talk to her, not in a kind & sensitive & soprano voiced way, just tell her matter of fact:
"... Just because I'm a married man doesn't mean I don't have sexual desires anymore. You seem perfectly happy to exist like this and you don't mind that it frustrates me that I can't have sex with my wife so here is what I've decided. We will continue living together like this but we'll minimize alot of the current activities we share because I need to start focusing on me now. I'm done with the bull$hit of chasing you & asking you for sex, if you really don't want to have sex with me then I'll just assume that part of our lives is over. FYI I recently met a girl who is interested in me and I'm interested in her sexually and I'm going to pursue it (you can tell her this happened during one evening where you went out by yourself like I told you to go out, no more details that that). I'm not going to go insane and not live without sex, I'm a healthy man and I'm not living without it, life is too short for me to continue going through this with you. No more cuddling in bed, going to the gym together, eating out, shopping, etc. I'm going to start doing things that make me happy without including you in everyone of them. You're not my wife, you're more like a gay friend and it's unattractive to me. Next year we'll talk to a lawyer and start the process of separating."
30 seconds of dialog and that's it.
No more cuddling in bed, sleep on your side of the bed, start detaching from her, start going out regularly, stop including her in everything you're doing - it doesn't work!
My last question in this long winded post.... When are you going to do any of this?