Potty Training is Making Me Crazy

Miss M SHOULD be potty trained.  She's highly verbal, huge vocabulary and enormous capacity for reasoning, etc, etc, etc.  You know what she tells me?  "I like diapers."  Why did you poop in your pants? Don't you want to use the potty like all of your friends?  "Nope.  I like to poop in my diaper."

ARGH.  I'm not sure how we got here.  I feel like we failed her at some point.  We've been trying intermittently for the last year, but she didn't seem ready, and so we've basically just let it go.  But now I feel like we are at the point that it's not a matter of being unable to do it, but rather a matter of unwilling, and I feel like it's something we did (or didn't) do that left us in this situation.

One of my friends, who has two boys who are now a few years past the potty training stage, has told me to simply forget it until she's ready and willing to do it.  She says she struggled with her first child without much progress, but let it go with the second child, and it just came naturally and easily to him.  I was inclined to take that approach, but, well--it's just not working.  I started doing that six months ago, and she's still not there.

Miss M turns three and a half next week.  She will start a new school in August, and I assume (but do not yet know for sure) that she will need to be potty trained to attend.  But more than that, it's just time.  She knows when she has to go.  She will tell you SOMETIMES.  More often than not, though, we end up with an accident.

Today I took her to a little water park for kids.  She was playing, and then something--the look on her face--tipped me off to the fact that she was pooping in her bathing suit.  "Miss M," I said, "Do you have to go potty?"  She agreed that she did,  but it was too late.  When I got her into the nearby bathroom, the poop was dripping from her diaper onto the floor.  Honestly, I just wanted to cry.  She was utterly nonplussed.  When I said we had to leave because she had pooped in her bathing suit, she simply said okay, and asked if we could come back later.  Then she promised she wouldn't do it again, like she does every time I tell her that she needs to tell me when she has to potty.

We're going to start a sticker chart later today, with prizes she can see.  I think I will put them up on a shelf, so she knows that when she gets enough stickers, she can have the prize.  She's not typically motivated by prizes, but it's worth a shot.   I have to do SOMETHING.  If anyone has a better idea, I'd love to hear it.