Guardianship responsibilities question; Can my assets be seized?

No they cannot take anything of yours if her name is not on it. But if you are acting as guardian, as POA for her you need to be very careful in the way you sign bills and contracts. Be very clear on the rules of that. You are basically signing her name, followed by your own with the words "as POA" or fact. It is crucial to know the rules when you do this.

Do not commingle anything with your mom. It blurs lines and could cause some issues.

You are not financially responsible for her because you are her guardian, however, you are responsible for her finances, meaning that you pay from her money for her care and needs.

They should not be able to take your assets or money just because you are guardian. But make sure you're careful about not sharing your assets or your money with your mother.