IMHO-

By having position HU and not betting the Turn you pretty much guaranteed your opponent would bet into you if a spade didn’t come on the River. He has to be thinking you bet the flop to get a free card. If you had an A (or even a J) you never would have given a free card on a 2-flush board.

Bet the Turn and he probably would have given it up. If he called and then bet the River, then you may have to think as you are probably beat.

SP