This might sound crazy, but to the outside world, that's how it looked like me and my ex were..
it wasn't at all, as rosy as it looked, just remember people are very good at putting on fronts, and you never know what's going on behind closed doors!!
Also men take up alot of time and enegery, especially when they are the father of your children - i remember when i was in labour the midwife saying, that the happiest and proudest mums she sees, are the ones who don't have a partner! and i can believe that!
don't be jelous, be happy with what you've got. You are clearly a very strong lady, you're independant, you actually don't need a man. You're child is a complete product of you, and you've shown that although you've been through all of that, you've come out on top!!
To me, she should be jelous of how strong you are!
Also when you have all that happiness and it's dependant on someone else, you depend on them not to make mistakes or make you feel down - when you do it alone, nobody can take the way you feel away from you apart from yourself!! So your happiness is more real? if that makes sense!