mm99,
I am in almost the same situation as you and I can totally understand how you feel. I found out my husband had changed on march this year and he keep on whatsapping this ex classmate of his all day long, all week long. I can also sense his change his attitude. Call it woman's instinct, 6th sense or perhaps my understanding of him, I immediately felt something is wrong and I confronted him. He admitted, and he also make the choice of choosing this woman instead of my daughter and I. Not once but twice when I asked him on 2 different timing. I was devasted.
I tried all ways to make him come back. I bare out my thoughts, I do all kinds of things, but yet he hurt me times and times again by whatapping her in front of me, and on one occasion I finally manage to get hold of his hp (He keep it besides him all the time in case I got something out of it), he even says to her "Nevermind lah, my wife already knows liao, I wanted to tell the whole world you are mine!".
He even says we shall just remain married, but what he do outside is none of my business. Imagine how selfish is he to say something like that?
Got once he says he will break up with that woman coz I was so devasted that day. I scold him and that bitch for breaking up our family, why they have to make me suffer the pain for the wrong they had done? What had I did to deserve this? I was never greedy, I never ask for alot of things, I support him whenever he's down or in need, I take care of our daughter and family well, why he still have to do this to me? Perhaps he's feeling very guilty thats why he says he will break up with her. We spend that weekend together, first time together after all this third party thing. But it just feels so weird, like he's just being with for the sake of being with me. But not because he wanted to. And all the while, he is still in contact with that woman, which shows he does not have the determination to save back this marriage.
As much as I'm not willing to, I bring up divorce, coz deep in my heart I know, even if I manage to pull him back, things will never be the same again. Actually right from the start I had already say to go for divorce, but I keep holding back hoping he will come back again. But times and times again he had proven to me that, how naive I actually am, to hope for him to come back which is seem so impossible, and he is still unable to give up on that woman. Don't see my daughter small small only 3 years old, one day she suddenly pop me this question, " Mummy, why daddy don't love you anyway?". Its affecting her.
So, I think for my case, the wise decision is to leave him and to give the full love I had to my girl. But I will still tell her daddy and mummy both still love her very much, don't want to deprive her of the love she deserved. Ultimately, the decision is yours. Unless he is really that hopeless, you can still give him and you sometime to try to make things work out. If really can't, its still not late to make a decision. Coz you know you had tried your best already.