Trouble with the Hag/Auntie Ethel as Paladin

When playing the game I came across quite the conundrum. I basically have three choices to make, either "kill her" (keep my 1000 gold lose on an extra stat) or spare her for the time (breaking my oath and forcing me to either pay the 1000 gold or change my build completely.)

From an RP standpoint it makes sense for my character to not spare her. From a gameplay standpoint I really want an extra ability point. I value gameplay a bit more but I made saves for all three options.

My question for y'all is what do you think is the best option?

I assume I can't break my oath more than once but don't know if this best place story wise to do it. I wanted to keep the option open to break my oath when only absolutely necessary. Will there be another point in the game where it may be better to break my oath other than this moment? (I don't care about spoilers)

They already patched the option to let your companion talk to her so thats out of the question.

Please let me know what y'all think and what you think my best options are, happy to answer questions.

Edit - I see that some in the replies have downvoted my reply to a particular comment. I don't mean harm, I'm both new to the game and the D&D world all together. I love RPG's and especially love to min-max, trying make the best/strongest builds I can when I play games, it's just the way I prefer to play my games. Just know I go into the game blind and really try to not look anything up. Passing up on a way to min-max isn't in my nature so I felt the need to ask. Have a great day : )