I'll admit, this is a factor in my choice of not wanting another baby. But on the other hand, if I was actually THAT desperate for another baby, I would still go ahead and have another. But I'm not. My son's birth, and weeks after, wasn't the best experience for me. I associated my body with being pregnant with a baby that ended up being born in a traumatic way, so I tried to get back to "myself" straight away, i.e. stopped eating and carried on using Bio-Oil until he was about 2 etc, as well as things that would be classed as self harm. The trauma fucked my head up basically!
However, I don't think women shouldn't be allowed to say this. It's not really fair to be expected not to care about your body, is it? I think you get the impression that just because you have kids, you should put up with it. Believe it not, there are women out there who don't want to live with a prolapse! But... Live with heartache for the rest of your life because you didn't want another baby because of further damage or... live with the potential damage and have that baby you've always wanted?
If your desire to have another baby really is that great, I don't think anything will stop you (unless of course there is a medical reason)
I've not had to exercise so can't really comment on that, but is there a way you could incorporate looking after her, or playing with her, while you exercise? Have you looked up exercises after a C-Section? I don't know but there might be something you can do specifically to re-build the muscles after abdominal surgery.
Of course your body will never be the same as pre-baby, blah blah blah, but you can always improve the appearance and your self esteem by looking after it.