I don't live on the road, but I am single. I have yet to have a relationship last a full year, but there are also no bitter enemies in my dating history. I think a large factor in the lack of longevity in my relationships is simply wanting different things in life than the women I've dated. I'm happy with my life and have no ambition beyond what I've already achieved. I chose a career path that I absolutely love, but doesn't earn me all that much money and has me keeping odd hours a lot of the time. The odd hours especially, can put a huge strain on a relationship. I'm not available when she is. She's not available when I am. When I have money, I have no time. When I have time, I have no money. Still, I can bump into any of my ex-girlfriends and be greeted with a hug and a hello. Most of them have gotten together with people who are a much better match for them than I ever could have been.
There are certainly times when I would like regular female companionship, but then I realize that I value the time I spend with just me so much that it would be hard to share living space with someone else. Now, If I found a woman who understood my need to spend time with just me, I could maybe see myself building a working relationship.
In the mean time, as with so many others here, I'm really not looking all that hard. If I meet someone and something happens, great! If not, I like myself well enough that I can be happy alone.