Triggering (Grieving): Alcohol abuse advice

[Magic.]

This is kind of a long one, so thanks if you read it all.

I have a friend in the UK, my best friend, who's just lost her dad to cancer. She stopped smoking (cigarettes and weed) because of his cancer. But now she's started drinking ...
When we were younger we always drank and she often got drunk. It was never seen as a huge problem because we were teenagers ... it was the binge drinking phase. As we grew up she drank less but still enjoyed drinking. About a year ago she started drinking much less as her dad gave up drinking for his health.
He'd been sick a few months when he passed away, and much as she wasn't ready for it she was there and oh so strong through it all. Since then she's told me several times that she has to go pick up her car because she got too drunk to drive. And last night a mutual close friend called me and said she'd had an awful night getting drunker than anyone's ever seen her in the 5ish years we've known her to drink during ...
Her dad's funeral isn't until Friday and I think knowing her that this is an escape, and maybe after the closure of the funeral she may stop or at least cut down. We're all worried that she won't though. She's living with friends at the moment and they asked for my help as we're still so close. I'm in Aus at the moment and all I could do was tell them to stay with her, make sure she doesn't hurt herself / end up in hospital etc.
I'm scared that it won't stop after the funeral ... how can we approach the subject of her drinking (after the funeral) without hurting her more? We just want to protect her ... there's nothing wrong with a 20year old getting drunk in my eyes, but she's at the point of having several bottles of wine to herself when she drinks, and I don't want her to make herself ill