I have to say that I seem to relate to you more than I relate to most of the people on this forum. Lots and lots of good people here, don't get me wrong. I just appreciate the position that you're in.
I have an amazing wife. She's beautiful (truly very good looking), extremely talented and musical, a nerd like me, and a wonderful companion. I love her so very much and am so grateful for her.
I also know that if she knew about my addiction, it would devastate her. I spoke with a clergyman about the issue, and he agreed it would be better to keep it a secret from her at this point, though I hope that down the road I have a chance to "retro-confess" after I get past the worst of this. Be grateful you have a significant other you can be open and honest with. As for Ms. Flying Pickle, kudos on your acceptance of Absolution as a person with a problem that needs some attention. Not an easy acceptance, to be sure.
It's an interesting situation you're both in. Absolution, you sound like you have a genuine desire to change and to be who you know you should be. I also suspect you have some of the same problem I do: when you're good at dealing with other people, when you're genuinely pleasant and caring and supportive and good, it makes it VERY easy to gloss over problems in your own conduct. I regularly get evaluated at work, and have realized that this is definitely the case. I'm pleasant to work with, so everyone assumes I'm as competent as I seem. I know better, of course. I know that showing up 5-10 minutes late every day, scrambling to be punctual and have my work done when it needs to be is NOT OKAY. But I still do it almost daily, because, frankly, I know I can get away with it.
The other day I had one of my supervisors mention that he liked me, but he had noticed a couple of things that I simply wasn't doing well. He acknowledged that I was pleasant and good at what I do, but basically told me (very pleasantly) that he'd noticed I was slacking and that there was no excuse for it, and then gave me a couple of weeks to turn things around before he wrote his quarterly evaluation.
In some sense, I'm STILL getting away with something, because he likely wouldn't have given me the chance to fix it if he didn't personally like me. But I digress.
It was awesome to be called out on my crap. Truly, it feels good to know that I have to fix it now or there will be consequences. I didn't like it at first. I was upset. I was frustrated, and I was stressed out. Not so much, now. I have since made progress, and that feels good.
You seem like you're asking for the same sort of situation, in a way. You request we don't go easy on you or minimze what you have done, and you are honest with FP in the hope that she will hold you accountable and you'll have something to balance out your addictive pull to be a womanizer.
So here's my 2c:
FP, hold him accountable for what he does. How to do that is up to you, but if he knows that you will do so, he will respond positively.
Absolution, I don't know what to say to you other than what I've just put above. If you acknowledge your own faults, that's awesome. Acknowledging how and why you've gotten away with them for so long is another thing that might be both humbling and helpful. I might be wrong, of course, but I wanted to honestly say what I"m thinking in hopes that it's helpful to you. I hope you realize that I bear you no ill will whatsoever in my criticisms! (You did kind of ask for them, or seemed as though you'd at least be open to them, from your earlier posts.)
In any case, you're obviously both very good people, and I wish you both the best and hope that you'll continue to progress together and support each other.