I could say the cliche "this is where God wants me" etc but let's be honest with ourselves, there are other reasons as well.
I have a few various reasons. 2 years ago I broke off an engagement to the only guy I had ever dated that wasn't abusive. It still however wasn't healthy. He and my Dad had major issues (and I'm an only child of a single father who is my best friend) and he also was disabled and didn't have a job so I was the breadwinner. Granted, that wasn't a huge deal, I didn't have a problem being the sole provider but at the same time, he didn't clean after himself...I'm off track
After that engagement was broken, I have been on ONE date in the past 2 years....ONE. And the fact that it was only one was because the guy lived out of state and it was just a nice get together rather than a date.
For awhile I could be fine with the singleness as it gave me and my heart time to heal, but after awhile I started enjoying doing what I wanted, not having to discuss any decisions I made with someone else and living my own life on my terms (which are God's terms)
So for now I'm single because I don't want to be tied down. I'm in graduate school, have a great group of friends, an awesome Church family and a job that pays well and has great hours and schedule. I don't have a need (or time) for a relationship. Do I get lonely? Sure. But it passes.