I think calling this woman's expectations for an engagement ring gold digging
Is it really that expensive?
Yes, she wants a diamond ring which costs 50k
That is really expensive. I recommend communicating this with them that the ring is far too luxurious and outside the price range of what you deem acceptable.
I agree. She's being unreasonable and she doesn't deserve happiness.
I know you're in a tough situation. I'd recommend continuing to try to work it out and hopefully she'll see reason in the future.