Bear with me while I try and explain my weirdness 
A family member has just had his first baby. I couldn't be any more thrilled for him and his wife. The baby is absolutely beautiful, and they will make such wonderful parents. I'm so, so happy for all of them.
Here's the rub. I'm a single mum to my three. They are good kids and I love them dearly. But when I think of this new baby, I feel slightly sad for me and my children too. And a tiny bit jealous. It's not that I want any more children; far from it, and I'm too old anyway.
It's just that a new baby represents a clean slate, a new and fresh start. And it makes me think that if I could go back, I would do many things so very differently. I'm a good mum and my children love me and think I'm the best. But in some ways, I've struggled. I put on a good show, but deep down this isn't really the life for me and I'm looking forward to one day getting my life back again. My own mother wasn't a natural, and I sometimes worry that I'm like her. I think a part of it is that I am feeling slightly demented by my 3 over the summer holiday! 
I'm sitting here crying like a total loon as I write this! I don't even know what my AIBU is exactly
In a nutshell, a new baby being born into the family has brought up some feelings in me. The feeling of wanting to do it again, but better this time. And seeing their happy little family unit has made me sad that my children don't have that any more.
Obviously I keep these feelings to myself.
Can anyone else relate to what I have written?
Thanks.