If you guys are good friends and you want to possibly save the friendship, you go to her. Tell her that with your boyfriend moving in, you've decided you'd like to just have him and you living in the condo. Tell her you still love her and that she can take all of October and November to find a place and that you will even help her look (if you want to help). Tell her "I know it seems cold and overly professional, but my parents are insisting that we put this in writing, so don't freak out when you see their notice to vacate in a few days. You still can stay until the end of November, but the notice just makes it all legal for their files and taxes." Of course, this assumes she is not on a lease.
If she balks or doesn't look like she's going to play by the rules, then your parents step in and lay down the law, talking with her personally about what the expectations of her are. Meaning, she leaves her area clean, she takes all her personal effects with her, she pays rent for October and November, she returns the key when she leaves, etc.
I do recommend that your parents change the locks once she's gone since you have no idea who she's given keys to. Like immediately - the day she leaves or with 24 hours.
As already stated, your parents are legally required to follow state law. In most states, this means a 30 day notice, or one full rental term. This puts her at the end of November before she has to be out. Some states are shorter, so it will be up to you and your parents to research this more if you wish to have her out sooner.
If she has a lease, then your parents can 'violate' her for moving in an additional tenant that's not on the lease. They can give her a notice that requires her to remove the brother or to vacate, usually in 3-7 days. The catch is that if she moves the brother out, she is legally entitled to stay until the end of the lease, unless she egregiously violates another term and doesn't repair it.
It is business. Politely give her a 30 day notice to leave. Keep in mind that if someone refuses to leave on their own, only a judge can make them. Your parents (the property owners) need to file formal eviction charges against her.
Tell your parents you want her gone or you will be looking for other accommodation.
IF she has no lease, you give her notice to vacate in accordance with state laws.
So I've been friends with my roommate for about eight years. We went to the same college and roomed together for two years. my parents recently bought an apartment for the two of us, she pays a very small rent. Originally it was intended for the two of us, but she brought along her brother and is sharing the room with him in order to save money.
Right before school started my boyfriend found that his housing on campus didn't go through and was without a place to live, so now we share a room. my parents are ok with this arrangement. However my roommate has been not very nice to live with. She complains about my cat, who i keep clean and pick up after, and complains about dishes and cleaning but never pitches in herself, in addition to being cold and uncaring. She's a pain to live with. How can i all her politely to leave? She doesn't seem happy neither am i.
