So sorry to hear about your husband's throat cancer.
To answer your question - on the tabs at the top you will see Forum Profile, click on that tab, then on the dark grey bar on the right-hand side you will see the Edit button. Click on that button and there in the User Account you can Edit User Information which includes your password. Don’t forget to then scroll down and hit the Save button.
Took me a while to find it too. Good luck with changing your password.

Are you okay? How are you both coping?
Maz