Hi, I am new here. I wonder if anyone relates or can help. This is a long post, I know. 

I have an alcoholic sister. She is 33. She drinks daily, has had a DUI, and even been to rehab. She has been one for about a decade now. It hasn't affected my life much until 4 years ago because we've lived in separate places and she's a functioning alcoholic (she can still hold a job). However, the past 4 years, she's wanted to move to my city (across the country) off and on, and I've let her stay with me and my other sister to help her out. These times, we've had some very heated arguments and tension because her drinking is right under my nose, and also has affected me. My other sister and I feel like she brings stress and drama because she can be unpredictable when drinking. She used to have a boyfriend that was also drinking daily with her, and he turned out to be extremely troubled and suicidal. They had a toxic, abusive relationship and I was witness to it because it was happening in 2 different places and times they lived with us. I actually started going to therapy because it weighed on me so much I needed someone to talk to. He died last year from suicide. I am more angry than sad about it, because he was extremely negative and abusive towards her, and she kept going back to him, even though it was unhealthy. It was a stressful time, with her also threatening to commit suicide and drinking daily, not sleeping, calling random people in her phone while drunk, etc. She was staying at my mom's and had an episode where she blacked out and apparently hung out with people she doesn't remember hanging out with until the wee hours of the morning. Because of it, her best friend decided she couldn't stay with her anymore because she has children.

My mom helped send her to rehab, and when she returned, she came back with a boyfriend she met in rehab. I found out she had relapsed, but my mom assured me it was "just to help her sleep". She clearly hadn't dealt with her grief and issues. My mom was excited about the boyfriend because it gave my sister a new zest for life. What they didn't tell me was that he was a heroin addict. She moved to my city AGAIN (this is a fourth time now/going back and forth to where we are from) and I didn't think I'd need to worry about her because she said she'd live with her boyfriend from rehab (I didn't know he used heroin until later). She didn't have a job or a plan, just government disability money and her boyfriend's rich mother's home. Lo and behold, they broke up maybe a week later. So my sister and I had to take her in AGAIN or otherwise she'd be homeless essentially. She has been living here about two months, without contributing financially, but looking for a job. She was sleeping in my bedroom and one day I found full vodka bottles in my bedroom. Up until that point she had done a good job of hiding it and sneaking it in her glasses.

I said that was my last straw and she couldn't stay with us anymore. 

Now my mom is not speaking to me, saying I'm "harsh" and "judgmental" and "lack compassion". She also is paying for everything for my sister and REFUSES to admit she is an alcoholic. "She's not an alcoholic," she says. "She doesn't get the shakes like alcoholics do if she doesn't drink. She uses it to cope and sleep." 

I'm angry, because my mom drinks wine every night and they've drank together before, and with her paying for everything and always cleaning up her mess, my sister never has to face the problem. 

I'm also angry because I was doing just fine living my life, and my other sister too, when all of a sudden I was in a position of having to take in my alcoholic sister or have her homeless, and dealing with her drama. And when she brought vodka into my bedroom and I finally created a boundary and said "no more", my sister and my mom paint me as a huge heartless jerk, even though I resent being in the position in the first place. My sister is an adult and I resent my mother implying I must care for her or look out for her, and the fact that only my other sister and I are the ones in the family that acknowledge she's an alcoholic. My father is totally useless and tends to just ignore the issue altogether or say "ask your mother". And he lives in a different state. 

I clearly can't get my mom to stop enabling my sister or for my mom and sister to face my sister's alcoholism. But, I now have a rift with them because I put my foot down and don't want her under my roof if she continues this behavior. 

Why can't my mom see that it's ok for me, as an adult, to say "I am not responsible for my older sister and she doesn't get to live in my home and abuse alcohol". My therapist (when I was seeing her; I'm not anymore) told me that was healthy. I can't stand this guilt trip I'm getting from my mom. I think she should support me and say that it's time my sister stood on her own two feet and started making responsible decisions (like not moving to a new city without a plan and not getting into a relationship with a heroin addict, who relapsed by the way). At the very least, I'd like my sister's storm out of my own life if she won't work on her own. I don't even like she plans on getting a place in my city because I feel like I'm still going to have to clean up her messes. 

Any advice would be much appreciated.