Idk what to do about my twin

She’s going completely off the deep end

She’s getting wasted on Sunday dinners with my family and then not remembering that it ever happened

She gets high to the point where she literally can’t function let alone see/stay awake

She made a second Instagram account and won’t have anyone she knows on it so I made a fake account so I can follow her second account and found out that on the second account she’s been posting things like how depressed she is such as “you know your depression is getting worse when you dad calls you to tell you about a new 1-800 crisis hotline”

THAT NEVER HAPPENED... I asked him about it!!!!

She also posted several pictures of her in just her underwear (not a swimsuit) and no bra or anything

My family knows about her smoking and drinking but don’t see it as much of a problem as I do and my parents are pretty much acting like they don’t see what’s happening because they don’t want to ruin the relationship they have with her

I broke down and told them about her smoking and drinking and they told me that it’s my job to fix it bc they don’t want to ruin the relationship they have with her

So after a few months I talked to my older sister and brother in law and they agreed that what my parents said was shitty but still nothing has been done

Well just about a month or so ago, I was watching my sister and brother in laws kids and I was in the middle of giving them dinner when my twin showed up and started rummaging through their fridge for food bc she’s done and spends all her money on weed and alcohol

She noticed they had beer and other alcoholic beverages in the fridge and wanted one but I told her if she was going to be around the kids with me watching them then she wasn’t going to drink... and then she got super confused and told me she drinks all the time while she’s watching them... I thought she was joking at first and laughed and she then got super serious and told me that my sister told her that she can drink while she’s watching her kids and that it’s okay

So clearly I talked to my sister immediately and to no surprise THAT NEVER HAPPENED

my brother in law was FURIOUS

I just don’t know what to do anymore

She’s getting so agitated over little things now... like over the weekend she was drinking at my parents house (again) and I asked who was going to take her home (she had friends over) and I asked if she needed me to give her a ride home and she flipped out!!

She goes “can you just stop worrying about me drinking for once?? Like it’s really annoying!”

Well sorry, no I won’t.... you already drive like a maniac when your sober by going 90mph and then other times not paying attention to what you’re doing and instead of driving like a normal person around a curve on the road... you drive straight and end up off the road in a ditch (SOBER)