LO is 23 months and definitely in the throes of the terrible 2s!

Any transition (getting dressed, getting shoes on, getting in the stroller) is met with SCREAMING fits, and throwing himself on the ground. I give him warnings (in 5 minutes, we're going to change your diaper), I try to give him control (which shirt do you want to wear, the blue one or the green one?), I try asking him to help me do it (can you show me how you put your leg through your pants?). None of it matters. It is BRUTAL--he gets completely hysterical and I can feel myself starting to get really angry/upset.

Any advice for working on this issue? Or any commiseration?