This makes no sense at all, your husband was cheating on you emotionally and you knew about it and from what it seems is that you would be okay if that woman came back in his life as you can't see him "BROKEN". I'm sorry but if this is true your husband is wacko and you too for caring for him when he was cheating on you. You haven't really told us why you were supposedly in the wrong and what drove him away from you. At the end of the day Cheating is Cheating, why did you let it go on for so long. You should have put your foot down and give him the love he was getting from where else. Now that you can't go back in time you should either try to mend the relationship between the two of you, or you should seriously consider whether this relationship should continue to exist.
OP; have you accepted that your relationship is just a foundation for your children and you are both free to seek emotional support/love/other from other people? Because if I'm honest that's how your thread is reading? If so if you are in an 'open relationship' your husband being 'broken' really isn't your problem is it? It's not like you are meant to take care of the emotional side of things if he is free to seek them outside of your marriage?
I have always told people tht u get one chance at life so live it or waste it..just don't drag it...for ur sake, for his sake and for ur children's sake don't drag it!
Ill tell u why im saying this:
i have seen children from a loveless marriage (my best friend) she incapable of loving people in a healthy constructive way, u guys think that ull put a mask on and ur children wont see the unhappiness than ur wrong. My best friend tells me her parents never fought but they never even spoke either in a way tht showed love and growing up she sensed that they both were under the same roof cuz of her and her siblings. Her concept of love is totally messed up and now that she is 25 is so scared of loving someone or be loved that she wants to remain unmarried all her life and open an orphanage somewhere in a suburban area. Point being spare ur kids all this and either love ur husband in away tht sets an example in their life or move away to set an example that one should respect themselves enough to walk away from anyone or anything that no longer serves u, grows u, or makes u happy! This goes for everyone in this equation u, ur husband and ur kids.
You probably 30ish or even less so u have quite a bit of life left to turn things around, i get that ur husband is strong/mature and a go getter person and u have personality flaws which probably restricts u from ever expressing the love and respect u have for him in ur heart an continue to live like cousins rather than husband and wife. I'll suggest sit him down, ask him another chance at this marriage, tell him the love u have for him in ur heart..tell him how much u have suffered in ur heart and ask for another chance and than consciously take steps to change urself, take initiatives u know he'll like.
Love isn't easy honey, we fight to get our love and u have him under the same roof and u throwing it away? all u gota do is prove it to him! The solution isn't to get him married to someone else and ruin ur perfect family, the solution is to grow a spine, take charge of the situation and make it a family it deserves to be..don't let it go so easy!!
With all sincerity i believe that Allah has bestowed women with a special kind of power which when used can turn hurdle around and when used wrongly can turn anything good into a complete destruction..its ur choice how u wana play with this power!
i say you leave him alone. if he fell for another woman, thats his problem. since your marriage wasnt based on love and you dont expect him to be faithful, then let him figure out his heartbreak on his own. he'll come to his senses with time. you can continue running your marriage the way it was before.
i think maybe you need to give him some time and try not to hurt him with your personality disorder (i think you said thats what it was called) traits again. slowly he will come back to you. you are very kind hearted any other pakistani woman would have let hell loose.