Your original post:
"When I joined this forum, I identified myself, completely without thinking, as someone's mom....
The funny thing is, I have four wonderful children, and Sophie is the name of my dog....
So it's a kind of funny/sad/pathetic/ "aha" moment.
I'm thinking of changing it."
By the way...
I understand why you might feel that way, but it completely makes sense to me. Being a mother is a wonderful and amazing thing. But it can't be ALL of who you are. There is too much pressure. No matter how great it is to be a mother, I would imagine it would also be overwhelming at times.
Puppies are a responsibility, but nothing like the demands of little human beings. When your dog gets upset, they eat your shoe or poop on your pillow. When your kid gets upset... they pick your retirement home with malice.

(At least, that's what I always threatened my Dad with).
I say... if you never had a problem with it before, don't change it out of guilt now. But if you choose to do so, make it for YOU.

That's what this site is for... your support.