My roomate bullying me, what should i do?

I got two roomates, one that just move in and the other roomate been here fot 3 months, thats the one i'm having a problem with.

The roommate comes at 3am, knocking ar my door asking for 20 dollars for a taxi because he has no money to pay it because he wasted hes money on cigarettes and beer and iphone 5

I give him 20 dollars then at 4am, he takes another taxi to stalk hes girlfriend house, he comes back, knocking at my door and the new roommate door asking for one of us to pay hes 72 dollars taxi bill, he was cursing, knocking at the door hard!

He runs away from the taxi, goes to a store, gets cigarettes but doesn't pay, he runs away from the store with cigarettes.

Hes girlfriend is the landlord of the house i rent a room at. I told her about the situation, she say she is sorry blah blah

But i want the roommate to pay my 20 dollars and the 20 dollars he broke my hair cutter. But he seems like a violent drunk addicted person, what should i do? I can't move out cuz i got no money for that yet. If anybody got any advice please help. I want him to pay my money and stop harassing me.

1. Forget getting any money back
2. Cut roommate off. NOW. Learn to deal with his temper tantrums when he doesn't get his way, but DO NOT give in (this will help you in the event you have to deal with teenage children -- trust me)
3. Leave a tip with the store and/or the cops about him stealing cigarettes.
4. Get a room at the nearest YMCA until you can get another apartment -- and talk to his girlfriend and beg to be let out of the lease early without penalty. If not, keep your mouth shut until the lease is over and find another apartment to cover you when the lease is up.
5. Start saving up for your move NOW. You need to get away from this guy As soon as possible.

First of all just accept that 20$ as a loss. Next, Never lend him money every again. Ignore him and if he ever gets physical with you call the police.