The meaning of "sick of"

Question

Can "sick of" mean ambiguous in this following example without further context?

My mom has been sick of lung cancer for three years.

I think this sentence can mean either

1. My mom has been mentally ill because of lung cancer for three years = My mom has been frustrated with/angered by/annoyed by lung cancer for three years.

or

2. My mom has been physically ill because of lung cancer for three years.

In modern English, "sick of" seems to be mainly more used to mean "mentally ill" than "phsically ill" like in this example,

I'm so sick of my life.

So, if we really want to make the sentence mean 2, it seems to be much better to change "of" to "with" as in

My mom has been sick with lung cancer for three years.

I want to know whether my thinking is correct.

Answer 1

To be sick of something doesn't mean to be mentally ill--it means to be bored or annoyed by something.

The sentence "My mom has been sick of lung cancer for three years" isn't really ambiguous, because anyone will realize that she probably doesn't find it boring. But it's not a correct usage. "Sick with" is what you want.

To be sick with is the proper preposition for both mental and physical ailments.

Answer 2

Yes, "sick with lung cancer" is much better. "sick of lung cancer" would mean "bored of lung cancer" in modern English, though people would understand what you meant to say.