Wish I could help 💔

Grace • cant wait to meet my little lady 🎀
Okay so this isn't really pregnancy related its just breaking my heart and I need to vent. My sister is 4 years older than me and we have always been SO close. My sister has been my best friend my whole life. Well when I started dating my boyfriend a little over a year ago she started seeing this other guy around the same time. He seemed okay at first.. Although he is way older than her and seemed a little off at times. Well after about a month she admitted to me that he is a convicted fellon, he actually has the most felons in my county. He apparently had recently gotten out of prison after being in there for 16 years.. My sister has a 5 year old son and was working as a nurse when she met this guy. It wasn't long before he became her "sugar daddy" a she put it and she quit her job and lived off the money he made. FYI he made is money by being a male escort and selling drugs. My sister told me is was just marijuana that he sold but I knew she was lying. Her and I stopped talking and seeing each other because every time I was over at her house they were drunk or high on coke and I was starting to realize my nephew was never over there. She would make excuses why I couldn't see him when I asked to and she completely pushed my entire family away. So now about a year later everything has blown up, I just found out that she hasn't seen her son in nearly a year and has living with his dad who hasn't been around since my nephew was an infant. (i got in contact with the dad and luckily they are doing great and I've been able to see my nephew again) Well my sister just started reaching out to me and my mom again. She's been asking me about my pregnancy and even said she wanted to come visit me (i live 3 hours away) and keep me company for awhile. I was stoked that she wanted to do this! But then I got a call from my mom and she told me my sister contacted her and admitted that she's addicted to meth. Her idiot boyfriend is addicted too and now they are both broke and homeless, they got evicted and the bank is trying to repo their cars but they haven't been able to find them yet. She told my mom that She doesn't want to be with this guy anymore but she is scared to leave cause he's crazy and he's nearly choked Her to death a few times. Now part of me want her to come and stay with me because I feel like she's trying to get distance from him which I think would be great for her. But then a much bigger part of me knows that even tho she's my sister, drugs have changed her and I don't necessarily trust her.. I know people with addiction usually aren't afraid to steal to get a little extra money for drugs and the last thing I need is to be robbed by my sister.. Plus I would be afraid that her boyfriend would be angry and come find her. He's the last person I want at my house or in my life especially when there's a baby on the way. I wish I could help her and be there for her But I just feel like i need to focus on me and my baby right now. I feel like I'm turning my back in my sister but I just don't want to risk anything...