It's okay to complain, OP, to UA, and you said you have. Good luck.

I would try to keep it short and stick to the facts.

I'd leave out "I just spent $8k in 5-months" because even if true, it comes off DYKWIA, which nobody likes that attitude, especially an anonymous CS agent deciding (probably on his/her own) how much sympathy to show you.

Basically, regardless of forum feedback, you "feel" that you have been wronged, and no one can tell you how to feel. Rational and irrational arguments basically have the same effect when it comes to one's feelings.

I think though, you'll find some "justice" here with the complaint you sent to UA. As long as you kept it classy.