Quite a few things hit me in reading your thread. To start with:
Six months is a short time...way too short of time to expect the other person to be fully committed into knowing that they love you. Most people don't like jumping into that level of a relationship in that short of time. Some do, but many don't, so to expect someone to be at that place in such a short time just because you were was a bit unrealistic.

Ok, alone that line, some people also tend to want the thing they can't have. If the person has problems with relationships in the first place, sometimes when the other person is finally unavailable, then they feel it's safe for them to feel their emotions. Those feelings may be real, or may not be in reality, but it's safe to express that feeling. Not saying that this is what was going on with your ex, but it's a definite possibility. The possibility that if you were to end up getting divorced, this ex may not really end up being there for you in the long run....the possibility is just as great that once you really would end up available, he really wouldn't be there because it's just as possible that he's only there because you aren't available.....something you won't know unless you get into the situation.....but the possibility of it being this way is just as great as the possibility that it isn't.

Ok, lets go on with the relationship you are in:
In other words, you become like the person you are around instead of being strong enough to hold your own opinions & values in spite of who you are around? So the only way you can be a good person is to be around good people? You have a problem holding to the values & feelings that you want yourself to have. Given that you have determined that you have this problem, I would suggest that even if you do get divorced from the person you are married to, that you stay alone until you can determine who you REALLY are & start to hold up your own values in your own life. I think in reality, you would be a better example to your kids by being a single strong parent than one that blows with the winds they are surrounded by. The important thing is life is that we need to define ourself by WHO WE REALLY ARE, not by who we are married to.

Yes, I think the marriage you got yourself into isn't a good one & I'm not going to say, "you made your bed, lie in it" because I don't believe that it's really the best thing for the kids. From what you have said about your marriage, it's NOT a good relationship & really isn't a healthy one for your children to be brought up in.....definitely teaching them values that I don't think are good for them. I think that the marriage you are in needs a lot of serious work to make it a good marriage (if that is even possible). I'm not sure that either of you are strong enough to do it without professional help. Only you can tell if the damage that the marriage is doing to your kids is bad enough that leaving is the answer.

You do sound like someone who is desperate to have love in your life & you are searching for that elusive LOVE.....definitely NOT the way you want to go into any marriage.

The marriage you are in doesn't sound like it's the best, but with the right kind of help for both of you, it could work out but it would take changes & work from both of you to make it work. I don't think that jumping back into the relationship with your ex even if you would get divorced would give you that elusive love you are looking for either.

I think you need some alone time with your children to learn for yourself WHO you really are & what YOUR OWN VALUES are & what your OWN THOUGHTS are. Once you figure out WHO YOU ARE & become the person WHO YOU WANT TO BE, only then would getting married to someone who really fits WHO YOU REALLY ARE might be the answer.

Just giving you more food for thought from feelings I got in reading your thread. I left my husband after 33 years. We were both engineers in our careers but he refused to communicate & even though being a nice person, he had spending problems that I allowed to rub off on me even though I knew better & I couldn't trust his answers to any of my questions as being accurate for basing my decisions on without it costing me because of his being wrong when he was sure he KNEW what he was talking about. Anger built up over the years to the point I was seeing red & fighting with him on everything by the end (still married only separated at this point because of financial issues). I know that staying with him & the fighting between us wasn't a good thing for our daughter & if I could do it over, would have listened to the little voice that inside of me told me NOT to marry him in the first place.

What I have found out is that after leaving him & going to a place completely new where I didn't know anyone, I have been able to become WHO I REALLY AM. I don't need anyone elses love to define who I am. Having friends who care & who I care about in a very family sort of way has been great....knowing that people care & are there for me the same way I like to be there to help others for me is better than anything love could possibly provide....because that kind of caring is a kind of love & can end up being more important to our own development of self than any other kind of relationship.

Hope you are able to figure your life out, but thought I would through out some other thoughts that seems like might not be thoughts you have considered before.