Awww Jesss, I kind of suspected you'd only seen the tip of the iceburg when I read your husband's fluff response the first time he got caught, acting as though this was the only time he'd EVER done it and gosh golly, his guilt was eating him alive and blah blah blah.
That just sounded SO contrived, I knew it wasn't true.
Good for you, installing a keylogger. You have a very powerful tool at your disposal - DON'T EVER tell him how you got your information!!!! Never, ever reveal your sources. All that does is tell him what NOT to do next time (if he's lucky enough to have you around FOR a next time).
So that's rule NUMBER ONE.
I'm not quite understanding what these lame profiles are for - are they on a sex hookup site, or are they on a dating site like Plenty of Fish or Match.com?
In either event Jesss, I think it would be foolhardy to believe he's never met anyone in person or hasn't cheated on you numerous times, sexually over all these years he's been doing this. This has been going on for a long time and to assume it's just been nothing more than silly little messages through a dating site or chatting on the phone would be pretty naive.
First, I'd find a lawyer who gives free consultations and book that free hour with him just to get an idea of exactly where you stand since you're a SAHM and have no income of your own (never a good idea - it takes away ALL your options).
Secondly, I'd start getting all my ducks in a row just in case this does lead to a separation/divorce. You need to start saving small amounts of money - $10 here, $20 there, so on and so forth. Keep it hidden and just for you.
As far as what to do about his long-running and illustrious online dating 'career,' I'd blast his sorry ass right out of the water.
I hope you've COPIED all the proof you found in his secret email accounts - make 2 copies and keep one safe in a sealed envelope with a friend or family member. You never know if you'll need it down the right. You need to be smarter than HIM, as painful as this may be for you.
If you're going to set him up for a sting, you can create a fake profile but don't make this girl over the top - that will look fake. Find an attractive random picture or two of a woman and create a profile with attributes you know he'll find attractive. Again, don't overdo it and make her into some kind of dream girl or he's going to get suspicious. Perhaps her story can be that she's recently divorced or out of a long term relationship and looking for 'friends' as she's not ready for a huge emotional commitment. That will be attractive to your husband as he can't GIVE anyone a huge emotional commitment. But you'll probably need to get a friend or family member (sworn to secrecy) to help you as he'll eventually want to talk to this woman on the phone. So it may require the cooperation of a friend willing to do this for you.
Keep copies of all correspondence, tape any phone conversations he and this 'woman' have (if you can), and absolutely set him up for a first 'meet' at some out of the way place - then show up and watch him squirm.
Honestly, you're not going to make him feel hurt or guilty or any of those things. If he hasn't felt that way all these years that he's been up to no good shopping around for cheap thrills, I don't believe he's going to have a sudden epiphany and realize how crappy his behavior has been. It's almost like he feels justified from what I've read in your profile - he's verbally abusive and something tells me he thinks he DESERVES to have extra curricular crap going on the side. All he did was give you a whole bunch of lip service the last time he was caught.
I'm really so sorry you find yourself in this position and I think you're VERY smart for keeping what you've found out close to the vest - until you're ready to use it. Good luck to you.