Things can end well, but that depends not so much on whether or not your hold your marriage together, but on how determined you are to get healthy no matter what happens. And with kids to raise, you have to commit to being/becoming a healthy person in order to raise them to be healthy adults, no matter what happens.
Go to therapy. Learn to listen to your spouse. Find out what is going on inside him. He obviously isn't feeling heard. On the other hand, one's spouse can't make them happy. We make ourselves happy or unhappy, and we bring whatever we are to the relationship. When someone admits that the marriage isn't working for them, it's time to simply be honest and work at building bridges. Work on building healthy communication with each other whether the relationship stays a married one or whether you end up splitting up. You will need to be able to communicate over the kids.
Communicate with your kids. They are hurt, and they know you are hurting. Let them know hurting is okay. Life is tough. It is okay to cry, and when you cry together, it is good to hug. Watch the kids for acting out, and stuff that shows they are hurting. Be sure to address the underlying hurts as best you can. It's hard when you are weak, but they are weaker and more powerless. Be sure to always let them know that you guys will get through this. Even if you are feeling lost and alone and totally uncapable, don't tell them all that. Tell them that you guys will get through this. It is hard and it is painful, but you guys will get through this. Don't make promises you can't keep. Don't lie to them. But do tell them you guys will get through. You will.
I can't give you a bandaid and tell you your marriage will work out and be better than it was before, but I hear at least one good thing. You didn't say there's another woman in the scene. The good thing is that he's being honest enough to say, "it's not working and I'm unhappy and don't know how to fix it." Alot of people don't say that. They simply bury themselves in another person to hide from that reality. Often when we throw in the towel, we are at the point when we have no reserve of strength left to work on the problem. That's why going to therapy will help. The therapist will hopefully find the good stuff, and help you guys take steps that don't take too much energy to work on, and the time apart gives you both time to cry, but especially to think. What is important to you about your marriage? What is important to you in a spouse? What drew you to him in the first place? How do you love him? How do you show your love? How do you receive love? Is what is good between you enough to stretch over and help you to conquer the part that is broken?
This is painful. There is no doubt. And whether it works or not has very little to do with any of us who will write in and say "we got back together" or "we didn't". What matters most is how much you love him, how much he loves you, and whether you are able to face the crisis, discuss your lives, allow each other the freedom and ability to grow, and whether, by reaching into yourselves, you find you still want and need the other in your life.
Honestly, my first marriage didn't work out. It was fine until we had babies, the first being a surprise. He wanted to "have fun" and play, and I was stuck raising two kids. In the meantime, he found other girls who didn't have any responsibilities, but that's not why I left him. I left him because I realized that we'd been down the road where he wasn't committed to the marriage once before, we'd worked itout, and it was happening again. And I knew my whole life would be that way, without security and without confidence in our relationship. I refused to have my children grow up believe that travesty of a marriage was all they could hope for in life. I have now been married for almost 20 years to my best friend. We met 1 year after I separated and divorced my spouse, we were friends, we dated, we split up, we became friends again, and dated again, and were married about 5 1/2 years after my divorce was final. At this point, there are some really dry periods, as well as some wonderful ones. I am right now going through a whole bunch of emotional stuff, and I feel horrible because he stands beside me wanting to fix it but he can't. I spend a lot of time crying. But no matter how hard it gets, we are committed to each other, and we are able to set aside the hassles and function as a united front for our children and anyone outside our 4 walls. I feel really badly making him feel so helpless, but he can't fix me. I have to find the fix. I am simultaneously railing against my own helplessness. I let a very successful career when we moved here 10 years ago, and now that we need that extra income again, I have been unable to even get an interview let alone a job. So I am hitting my head against a wall, because I have all the ability to change things, and still I can't seem to do so.
so what's going to happen with us ? We're "going to the mattresses". Financially, we're hunkering down and logging everything we spend, so we know if we can save any more than we already are. We'll get through this, but I am feeling hopeless right now. It hurts, but I know it's temporary -- even though I can't see the end of it right now.
and that's what I want you to be sure you hear. THIS IS TEMPORARY. Yes, it hurts like hell. Yes, you cry every day. Yes, there are also some good things happening. Your kids go to school each day and are learning things, making friends, being friends to those who need them. You have a job and if you need to might be able to add hours/ adjust hours should you end up splitting permanently. You have a separated spouse, but he is willing to go to therapy with you. That's REALLY BIG. Lots of guys won't go, because they don't want to think they might need help. And honestly, it's kind of good to be separated while you work on some of the stuff that's caused the current situation. You each have rooms where you can go and hide and cry. When you are married, you don't have that private space because you share a bedroom. There's nowhere to hide. You have time to collect yourself, time to think about your marriage and yourself. You have the power to make this an incredibly creative time in your life - regardless of the outcome.
Just keep plugging along -- one day at a time. one baby step at a time. Crawl when you can't walk. Cry and punch the pillows. Take walks. Do something good for yourself. Hug your children. Tell them you love them. Remind Dad, if you need to, to tell them he loves them, too. One day, one baby step, at at time. Each one brings you closer and closer to feeling healthy again -- whether the relationship remains a married one, or whether the relationship changes to being more remote. The goal is for each one of you to become more healthy than you are now. And then, from a position of better health, does the relationship continue to work as a couple?
That's the future. Right now you need to survive the pain, and you need to learn to communicate and listen to each other, which therapy will help. You need to support each other. Remember the old line, "If you love someone, let them go? If he comes back, he's yours. If he doesn't, he never was?" Well, I wouldn't simply "let him go", but I would give him the freedom and support him having that freedom, so he can discover himself again, and discover for sure whether he is capable of being the person you need him to be. Marriage is always "all about you". It's never all about me, or it won't work.
Most of all, commit yourself to God. Commit your kids to God. Commit your husband and your marriage to God. He is the only one who knows the future, and he loves all of you. Just cry out to him in your hurt and frustration, and know he is listening. Even when your mad or hurt or lost. He's okay with you the way you are, because he made you, you are HIS child, and he loves you.
Hang in. I'm rooting for you.