She didn't break mentally, she reacted how soemone that has no striking defense, no head movement, and no answer for anything their opponent had would react.
She felt her power, got dazed, because Amanda hits harder than anyone in the division, and she took the full force of the shots, because she has no skill, and doesn't know how to roll with a shot, and is literally too slow to even anticipate a hard shot, and brace herself for it.
It's like she thinks she's strolling in the park, then BAM! she suddenly gets hit. That's how slow her reaction time is. And how sorry her stand up is.