I was a single mom until my son was five years old, then I got married. Although I won't pretend for a minute that raising kids as a couple isn't a million times better than doing on your own for most things, there are certain advantages to being a single mom.
The most wonderful thing about raising a child alone is that you are THE authority on everything in your child's life. You get to make all the rules and know that you're the one carrying it out. Take whining for instance. With my son, I was extremely successful at quashing the whining at a fairly young age, but doing the same things that I did with him are NOT working with my daughter. I know that a portion of the problem is that every child is different; however, I know that part of it is that Girl is "daddy's little girl" and he both dotes on her and spoils her to death.
I often talk to him about trying to get her to stop whining, and he hates it as much as I do, he's just not as on board as I need him to be. So, the whining continues. Everyone needs to be on board, but when it's just you, everyone IS on board because you are everyone.
Another benefit of single parenthood (although this only works if you are absolutely alone as I was) is that you get to pick where you and your kids will spend holidays. No splitting your celebrations and spending an absurd amount of the day driving. In addition, you develop a very close bond with your kids. You never hear "I love Daddy the best-est." You get to be the best-est always because you are the only one there.
Of course co-parenting is awesome too. There is always someone around as amazed as you are at lopsided hand-turkeys and poop in the potty. When you get to the end of your rope you can shove the monkeys off on their daddy, and if your friend needs you to go out, you don't have to scramble to find a babysitter. In the end, I am much happier as a co-parent, but being a single parent wasn't that bad either.
6 hours ago