I have 2 people staying together who are both on a lease. The one person pays all the rent from what I understand and she is trying to get rid of I think an old boyfriend that is not working out. Both her and him are on the lease together on a month to month lease. He is refusing to go because he doesn't have anywhere to go and he may be a deadbeat but not sure. She wants him out of there ASAP but she wants to stay. I know I shouldn't get in the middle of this because the rent gets paid etc. but wondering the best way to remove him while still letting her stay. She probably doesn't want to give notice and go thru the hassle of packing up all her stuff (she has kids) just to then move back in; but even with that he may not leave and be the only one left and then I have to evict him on my own.  She wants to know if I can just write up a new lease with just her on it and then she can get rid of him but I would think he would have to sign something saying its OK to terminate the lease. This is in NJ and I know I should consult my attorney and mostly likely will have to but trying to get any ideas before I need to start that.

Being kinda an expert on dysfunctional relationships (Just ask any of my EXs). Just keep in mind they can be badmouthing each other all over town, he can be slapping her around, she can be cheating on him, and yet they both love it and f like rabbits. 

Cops can be called, one of them can get looked up, and they can be having passionate "makeup sex" and professing their love for each other within hours.

Especially if he is a narcissist, and/or she is a Cluster-B personality type. (Think Blanch Dubious in A Streetcar Named Desire)

Really the whole situation sounds like treading on thin ice to me

I agree. I just don't want to send another lease excluding the person she wants out. I agree she may be just saying stuff also. My position is really this is their problem not mine because they are paying the rent on time with no other issues. I will see if the issue goes away but probably sooner or later it may become my problem. The best thing maybe she moves out anyway but then I may have to evict him if he doesn't move out as I don't think he has the money to pay the rent. I'll keep monitoring but not try to get involved and see if they can work something out.