A tricky conversation to navigate. You also bring up some good points about entering this big boy pool carefully. Better to learn the ropes with a small amount than a significant sum of money. If you lose your keys there is no help desk to call and bring your account back.
My own wife will keep dismissing decentralized money until I am able to buy a house or something like that. She is ultra-conservative and risk adverse financially. I, on the other hand, am working towards getting as much of my earnings via non-$$$ means as possible.
I'm hoping coinbase steps their game up here in the near future. I've been mostly happy with their service until recently.
RE: Explaining Cryptocurrency to Your Significant Other