Uncle in Home; Aunt “fell in love”

My uncle and aunt are still married. My uncle has dementia and lives in a home.

My aunt and uncle (blood relative) had always told my dad that they intended to leave their money (they inherited some family money from my grandparents) to our family. Around $2M.

However, while my uncle has been in a home, my aunt has fallen head over heels for a guy twenty years younger (she’s 86). I feel like she’s the target of dirty intentions here.

She essentially controls her money, obviously, and she’s now told us that she intends to leave everything to him.

First, I’m pretty sure we have no options, correct me if I’m wrong.

Second, she just went into the hospital this week. What would happen if she (god forbid) passed away? Would this scammer just leave my family with all my uncle’s medical bills?