I’m no longer getting my sister and brother in law birthday presents

For the past few years I would gift then with a $50 gift card, same with Christmas.

And for the past few years I’ve only received gifts twice. And I’m tired of gifting being one way.

They have had a history with financial struggles and I don’t have nieces and nephews like they do, so I felt bad and gave them presents anyways.

But lately it’s frustrating. I’ve paid a vet bill (they did pay half back but I’m not expecting in return) lend her $20, $30 and more money and received nothing in return.

Then I received a message from my sister if I wanted to pitch in for my BIL’s 40th. I said “no” and was made to look like an asshole. She cried to my dad who almost always takes her side and reminds me “how good” they are to me and I should be more empathetic.

Am I being a dick? I always question myself, but feel used. Combined they make more than me but are always struggling.