It would be my duty to tell them, even if it strained the relationship.
I would tell them. Several months ago a dear friend of mine who had serious health issues would buy someone who was living with a friend of hers alcohol and cigarette about once or month or so.. She was defensive about it when I said that she shouldn't be buying this for him. Let him pay for his cigarettes and alcohol, I told her. She thought I was being judgmental about the situation. This dear friend had very little money for herself. When she told him she could no longer do this for him, he wasn't so chummy with her after that.
When my friend became very ill, she realized that she'd been taken advantage of by this person who told her that he would be there for her. He wasn't there for her when she got very sick. He might have visited her one time when she was ill. When she died, he was nowhere to be found at her funeral or celebration of life get together. He probably had an excuse for not coming.
Be prepared to lose both of them.
Well maybe, just maybe, the person being taken advantage of knows it, only won't admit it. You are telling that person something they don't want to hear. And, the person doing the taking advantage of, doesn't want you ruining his/her thing. So, tread carefully here. Often the messenger is the one who is sacrificed.
Sorry to hear that.
I've always kept quiet even if I knew.
If it would happen again, I think I would end up saying it.
if i thought they'd listen to me
if they really trusted the person who was taking advantage of them, they might resent my interference
Am I the one taking advantage of them? If yes, then no.
OK, I guess I should type s l o w e r.
What didn't you understand?
tell them and make them listen