I have been living with my roommates Karen and Natalie in a three bedroom place for the last 6 months without much of any conflict. Our lease continues through August and we had already planned on living in our current place through August of 2020. We live in a college town which means property management companies start advertising properties in January and February, so to secure our unit for 2019-2020 term we had to renew our lease in January. 

Natalie is graduating this year and is not renewing to live with us for the 2019-2020 year which we have known from the beginning and agreed to which is all fine. Now, Karen has decided that she suddenly wants to transfer schools and will no longer be here for the 2019-2020 year. This transfer is not so she can change majors, it is to a different campus under the same school and the classes are 90% the same. She does not have friends or family that lives out there so it's not to be closer to them. Rent is also a lot more expensive in this new city she is moving to, so this move is not about saving money either. She has joked that she's moving to this new city so she can eat chicken  from this one food cart every day. This idea for her to transfer came up only a couple weeks ago after we made a day trip to the city that the other campus happens to be in.  

I am frustrated with this because Karen on multiple occasions made it clear that she was going to live here even through 2020-2021 and we have already renewed our lease for the next year. I brought this up with Karen and she does not think this is an issue because she can just find a person to sublet. While this is true, I feel like it is unfair to leave me to live with two strangers and try to get them to pay rent and utilities on time when I had agreed to live with Karen specifically. Our roommate Natalie had been a craigslist rando, but it was fine because I knew I had Karen to help cover rent or bills in case Natalie turned out to be a flake. Now I might be living with two total strangers who may or not pull through on paying rent and being clean and good roommates for seemingly no reason. Am I just overreacting and being an asshole right now?