<human>: Can you give me the gist of the text in a nutshell?

My sister is in another country atm, she has a baby(3 y old) with this guy but turns out he isnt around, he likes adventures and parties and he is still moms boy so they ended their relationship.
Now she lives in this one 2 room apartment, pays rent and works 8-10h a day.   

She is really moody btw, obviously working every day gets to you.  

She often asks me to come over, stay few weeks and look out for her kid/baby.  
Now time has come for me to leave home but she wants me to stay more but that wasnt the plan, again, she does this often.

The thing that bothers me is how she likes to say stuff like "if you leave, i have to quit my job and take care of the kid, but if i lose my job I lose my Visa so I gotta go back home and what kind of life will I have" and that then makes me sad and all caring.  
She likes to use my good will like that to get what she wants.  
She does this with others too, I saw it.  

Now the thing is, my BF came over and he was here for few days and he saw her do this often so he confronted her about it and said she is mean for doing that.  
He said it in very calm way tbh, he was in attack mode but wasnt yelling, she was yelling and smacking stuff around the room tho.  
He spoke the truth, I cant blame him, he is real person, always speaks his mind and tries to tell the truth, but I also would like to know did he do the right thing ?  
Any opinions ?
<bot>: Sister uses peoples good will to gain what she wants, bf confronted her, they argued, I need opinion on situation.