Man don't feel good it is because counselling seemed like having to recongise being weak or unable to work things out - ego problem for a man.
I have to say one thing: You made a mistake, but you continued to move blindly towards it - you have no turning back. Mistake started when he had an affair with him.
Both of you needs serious heart to heart talk with one another. Problems lies within suspicious and mistrust - something that you cannot work out without communication. HE has to WANT to work out this marriage together with YOU. If not, it is like catching fly in the air - nothing works.
What must be communicated?
He already stated that his only feeling for you is responsiblity - which is not love. Ask him whether he wants his marriage anot if he do not have this responsiblity. It is totally useless trying to preserve relation that the flame has already snuff out. If he doesn't want to work for this relation, but instead choose to run away and find other woman company. There is little you can do, perhaps other professional hotline may suggest some ways or method.
After that initial phrase, the next thing is that the both of you have to get matured. Stop all these suiciding, email mistrust all that crap. Both of you are already MARRIED, therefore act like one. If he wants to make this relation work - he has to stop flirting outside, gradually change his negative ways of doing. You have to make it gradually change, not immediately: things don't change overnight. and you have to HELP him change too. Guide him along and move along with him.
For you, do keep a distance with your ex. I know you still have feelings for him but this is the route you chose to go. You have no turning back - regret isn't part of you and you must move on. If you should dwell on past - this marriage will fall because now you recongise this crisis and wants to solve it. If you don't want to: who else will?
And for the BOTH of you: Learned to speak like a married couple of understanding and respect. Never raise your voice to get your message across: speak and communicate properly. Don't suka suka say want to separate want to divorce - Damn childish. The both of you are alright with it, yes no doubt. What about your children? (Noticed i used the word 'both of you' and 'your') Can they voice their view? NO!
My advice is still the same: Settle those issues I mention above and seek professional help. Cyber advice are only words you see and how you interpret: solid face-to-face are still the best way to counsel.
i think we are trying to get each other's attention 
