Parenting is a spiritual journey that you enter when your kids are born. The relationships you have as parents may change over time, but your parenting is a huge part of what gives your life meaning. To me, my kids are everything. And to my partner, my love of their kids and their love of my kids, is unfathomable and wonderful when it happens.
Defining a "single parent": Dads and Moms who have sole responsibility (not custody) for their kids at any time during the week are SINGLE PARENTS.
You're going to have to be active in participating, in saying hello in real-time, and not using "online dating is so bad" as an excuse. I know I do it. But let's get out there together, okay?
I've found it very helpful to remain in the present moment when dating someone new. Try NOT to jump into the future scenarios, the "what ifs" and "what abouts." And when you are thinking that you both want the same thing, do some reality testing.