[BOTW]

Email and ask how she's doing, etc.

Next email, say "I like/care about you and if you ever need someone to talk to, feel free to contact me."

Best thing you can do for someone with problems is be there for them if/when they decide to ask for help. (If they never do, you can't save them. If they are seeking an 'enabler' you'll see that quickly as well.)

Confrontations are for people close to the problem, not for acquaintances.

Or, get drunk, then call her.