OK here's my story. Sorry, it's long!
My DP had his kids very young and when we met, his were in their mid-late teens, mine were still primary age. All his adult life he had been married and parenting his kids. He had alsways dreamed of working abroad to further his career and braoden his horizons.
Then he met me. We fell in love (madly) and were very happy together. He still had this dream though.
After 2 years of us being together and him having sole custody of his kids, his kids moved away (abroad) to live with their mother and his "dream" resurfaced. We talked about it a lot and it made my stomach churn every time it was mentioned.
Eventually he told me he was going to apply for jobs. He felt that he had not had a chance ever to just go off and do his thing and the only think keeping him in the UK was me (which was a big thing for us both).
There is no way I wanted to move abroad. DD2 had just started school and tbh I wouldn't dream of taking them away from their dad. As it happened, the area he was going to (middle East) would not have been possible as we are not married.
Anyway, a year after deciding what he wanted to do, he got a job. I am not exaggerating when I say that my heart broke and I honestly felt like we were over. He would be away for 10 weeks at a time, back for 10 days :(
He assured me over and over again that he loved me and was not leaving me. I was broken hearted.
That was 3 years ago and we are still very much together :o
Admittedly, he is on a bettr rotation now but we make it work bcause we both want to make it work. We speak every day. The time we spend together is very special and precious, and we are closer and happier than ever.
I also realised that a mooing, weeping, pining woman is not that attractive - why should he want to come back to me. Instead, I embraced my time on my own. I see my friends, work hard, concentrate on the kids and hog the bed. I have the best of both worlds.
I am currently counting the days till he's home (9!!!). I'm not saying it's not hard. It is. But it's do-able and it's not forever.
Maybe he's a good'un like my DP and when he says he's not leaving you, he means it
It can work. Why not see how it goes. If it's not working, then call it a day. Don't condemn your whole future life on the basis of a few years of not being together every day.
In the meantime, I do sympathise. I remember only too well just how you feel now.
Good luck and feel free to ask any questions you may have!