Not sure if I should let go..

[lekker01234]

I have a friend who I have known for about a year and a half now. I met her while she was working at a bar and soon after I would visit maybe once or twice a week. She is an attractive girl so ofcourse she gets hit on a lot. That isn't the issue or problem. She moved here about 2 years ago and lives with her brother. Her brother, how do I say this, is not the most reponsible type. On more then one occassion I've had to help them with their water bill since they couldn't pay it. She seems to be the only bread winner now since I don't think he works. She started to work at a new bar for about 8 months now. She has befreinded the bar tenders there and meets a lot of new tourists. I've slowly began to realize that after work, the bar closes around 1am and on weekends 3, she would go to this other bar that is open till 5 am. Now going out for drink after work is a normal thing but she goes there almost everytime after work for 2-3 hours at a time. I am worried that she is becoming an alcoholic. The other thing I have noticed is that her personality has changed. She isn't as open to me anymore which makes me sad but it is what it is. I've noticed also that she takes guys, mostly tourists, to the bar, and has them pay for her drinks. Usually she goes with another girl friend that works at the bar but I have noticed more and more that she has the guys take her home. I've also noticed that she has befriended the owner of the bar that she stays out late at and becomes, how do I say, a little overly affectionate since he gives her free drinks. Now non of her actions are any of my business but since I respect her and care about her should I intervine and talk to her about it or just let it go? I am worried that maybe she has also become a prostitute in order to payer her bills. I have never slept with her or kissed her for that matter nor is that my intention but I feel that she is going down a really dark road and I don't know what to do. Any advice would be helpful.