[PencilAndPaper]

Forget the ring. Its a thing. Take the extra money and take a pre-wedding trip to Central America! Memories dont get lost down kitchen drains (at least until the alzheimer's kicks in).

If my BF wasted thousands of dollars on something I might lose and something that will probably prevent me from easily sliding my hands into the pockets of my somewhat tight jeans (rings with stones are super annoying that way), I would second guess becoming financially united with him, but thats just me.

Dont get gobbled up by the consumerism surrounding weddings and marriage. Your GF doesnt want a fancy wedding and expects a cheap ring. So, thats good, she sounds cool. Dont tempt her to become a bridezilla. This is how that starts.