Look, if we are getting pedantic, ‘I feel so taken advantage of’ is not just a problem of a dangling preposition.
It is grammatically incorrect anyway.
Firstly the word ‘so’ cannot be applied to a verb in that way despite it’s popular use amongst teenage girls.
Even without the word ‘so’ – it should read I feel I HAVE been taken advantage of.
Also, bombmaniac, for someone who consistently misspells the most common word in the English language…….;-)