My 28 month old is really struggling with a behavior (and has been for about 2-3 months). He only really does it with me or DH (not with my parents), and mostly with me. It usually goes down this way:
Me: Do you want to try potty?
LO: Yeah, try potty.
(We walk toward the bathroom)
LO: No try potty!
Me: You don't need to go potty? Ok, let's go XXXX.
LO: Yeah try potty, try potty.
Me: Ok, let's go try potty.
LO: No try potty! No try!

At this point he is in tears, and it spirals downhill from there. He will neither go potty nor not go potty. Today it happened at his soccer class. I calmly said (as I normally do), "if you need to go potty, we can go potty, and if you don't need to, we can go back and play with your friends." It does absolutely no good and he just keeps going back and forth between trying and not trying and he becomes a big mess and I get frustrated. He isn't just messing with me (I don't think.) My impression of the behavior is that he legitimately can't figure out if he needs to go or not, and doesn't know what to do with himself, then gets worked up.

I've tried distraction, holding him calmly, making the choice for him (your feelings seem really big right now, so I'm going to choose playing with friends), etc. Nothing works. It usually ends with him totally in tears but finally half-heartedly doing one thing or the other. Today, though, it was pretty much the end of his participation in his soccer class.

It's not always about going potty, but I'd say 75% of the time it is. I've tried to make it really low-pressure and never force him to try, but it doesn't seem to be trying that bothers him, just this indecisive middle ground. Sometimes it's about eating a meal or going somewhere.

Help!