@hawkeye10,
Betty, Hawkeye in a way has it right, but largely his comments I see as unfair, because you are female, and generically (and genetically) speaking, most womens emotions behave differently in these situations than mens.
What you need to realise is that it is well and truly over between you and him. By what you've said, you may not want to be hurt by him again, but a part of you still craves him (or the connection you had with him, or similar, but it still ends up the same).
Let me put it this way - if he started chasing you again, saying how much he missed you, and how much of a mistake he made, and that he should never have been so much of a fool, but he's realised he can't do without you...would you weaken to him? IF you did consider going back to him, you wouldn't be understanding this guy in the least (he was married and having two affairs at the same time - that you know of). He was having two sexual relationships at the same time within his own office - do you realise what kind of guy does this?
On a deep and complete level, he is not compatable with you. He is like an addiction (of any sort)- gives you the great highs but can destroy your life.
He will destroy your life because he has no respect for you (none, zip, zero). I mentioned that people engaged in affairs lose respect for their spouses - but in that case, respect is categorised - you don't (and can't) respect your husband for believing your lies, or for not seeing what's going on, but you can respect him for other things (maybe he is kind in other ways, or socially popular or some other). For this guy at your work - your main relationship with him is that of prey, of a thing to be hunted for sex. He says the words, but they are empty, only serving to satisfy his lusts. His respect for you is actually next to non-existant...you were just an means to an end, so long as you amused him.
He may have used the 'my marriage is unhappy' line on you - and almost every single guy that has ever engaged in an affair with a woman who was cautious about engaging in an affair, has used that same line. He no doubt used it with the other girl at work as well.
What I'm saying is - you need to understand men, and the types of men out there, and that this guy is deeply incompatable with either you - your self esteem and your (overall, longterm) happiness.
He's not going to change for you, and has likely been engaging in many more affairs than you are aware of, over a long period of time.
Lastly (sort of lastly), his initial path down this road may have started with a similar attitude to where you are at now...peoples beliefs change with their actions. If a persons behaviour goes against their beliefs - the first time they can talk it away, the second time they hop to and fro, and by the third time, they are talkng themselves into why their behaviour is right...enough times and they come to believe their behaviour is truly 'right'.
There's a likely pedophile on these forums who started of stating he was attracted to (only just) post pubescent girls, and he was able to argue black and blue with great articulation why (if they consented) it was okay for him to chase them and have sex with them...it didn't matter how many arguments people put against him he found what he believed was a justification that argued their 'positions' away. I mentioned that he did this and that he was likely to progress to children and when he did he would come up with justifications for his tasted then too, and he denied this. About 2 years later, I found him posting about how pedophilia wasn't wrong, and despite people giving him very good reasons, he once again, argued black and blue how their stances were actually in error....and that is what I mean by peoples beliefs change to suit their actions (whether that action is right or wrong). Not calling you a pedophile - just giving you a warning of how the mind works to accomodate our behaviour, even when something is clearly wrong.
This is why it's very important for people to stick up for themselves - because not doing so leads to your mind justifying why it's 'not important' to do so...which if you don't stick up for yourself over and over, often leads the mind to believe 'it's not important because I'm not worth it'.
The second time is easier than the first, and the third time is easier than the 2nd. So be aware of who you are, and respect yourself (and others too, but yourself first 51/49).
...ugh I'm long winded !