I went to market with my wife to buy things for our new born baby, after my wife selected baby things that Worth thousands and I paid with my btc,the transaction was very easy and faster. When we returned home ,she asked if you die can I achieved your btc or continued with your account? Because it's very easy and faster in trading and transaction.
Sure she can use your account once you die or even when you are alive, if you share your private key with her. Anyone who has the private key can spend withdraw funds from your wallet. I think you should write your private key on some paper and keep it save in some documents. Also tell her that if you die, she can use this private key to access these funds.