Not sad at all!
Not all single moms are doing it on their own. Whether it be a good social network, close knit family, or any number of small blessings, things can be great.
My stbx is a huge part of DD's life. We say she has two parents 24/7, no matter who's house she is at. We work together to make sure everything she needs is taken care of and she has a wonderful, happy child hood, even if it is at two different homes. I often go to his house and hang out when she is there, and he does the same here.
I do get frustrated that I have so little time with her between working and her going to school and sharing split custody with her father. But she is thriving. That is what matters. I miss her terribly when she is not here, but that just me being selfish, which is not good for her.
Being a single parent pretty much feels like any other parent. There are even some married parents that have it harder. Extreme conflict with a spouse or living in an unhappy home can make things much worse.