What should I do?
 

So, my best friend is an addict. And I don't really know what to do. She knows that she is an addict, and wants help, but is in a toxic relationship where her boyfriend doesn't want to quit.
From my experience two addicts together just don't work out. They're relationship revolves around drugs and thats all they really care about/do anymore.
The other day I found needles in their car. They went from snorting pills, to now injecting them.

Me and her brother are close, and I've been debating on telling him or not. I constantly worry about getting the phone call she's been arrested or has OD'ed.

She recently got kicked out of her house and is homeless, so maybe this would be the right time to tell her family. I don't want to lose her friendship, but I would rather that then her dying/in serious trouble.

What should I do?

By telling her family (her brother) you may be doing her a big favor. It's only a matter of time before something bad happens as a result of her addiction. If it were me, I'd tell her brother.

I second Least. She won't be much of a friend if something really bad happens to her. You can compare it as if she is blind from the addiction and cannot see. Be her eyes and her friend!