Having a friend for a roommate may seem like a perfect idea, but sometimes it just doesn't work out. If roommate relations are making a friendship go sour, it might be time to rethink your living situation. However, kicking out a roommate who is also your friend requires special care and sensitivity. Preserve the friendship with a tactful, helpful approach.
Broaching the Subject
Approach the subject of changing your living arrangement in a positive moment. If necessary, create such a moment by making plans to do something with your friend socially. Have some fun together, outside your home if need be, to remind both of you that your friendship is still worth preserving. During or shortly after this, tell your friend that you don't think living together is working out for both of you. Point to frustrations and difficulties you've been facing in the past if your friend is surprised by this revelation.
Preserving the Friendship
Explain to your friend that it's important to you to do what needs to be done to preserve the friendship and that you think changing your living arrangements is necessary for that reason. Tell her that two people who make good friends don't necessarily also make good roommates. Let her know that you don't like how strained and uncomfortable living together is making your friendship.
Who Leaves, Who Stays
Unless you own the house you're both living in or otherwise have more stake or legal control in it, respect that neither of you has more right to stay. Open the discussion by asking which of you will leave and who will stay. However, you can try to convince your roommate to do the leaving if you can make a convincing argument for why it's a good idea. Come to the conversation with suggestions about who can take her place and reasons why it might be more convenient for your friend to live elsewhere. Promise to help with the process of moving out.
Ask your friend to agree to a timetable for moving out. Inquire as to what his requirements for a new home are and help him look. Hunt for the best leads you can to give him some incentive to move forward quickly. Assist with the actual moving process and encourage mutual friends to help out, too. Strive to make the move as painless as possible for your friend in order to get it done promptly and smoothly as well as to show good will and help preserve the friendship.
Post Move-Out Bonding
After the move-out, let a few days or weeks pass to clear the air between you and your friend. After this, initiate some bonding activities together to establish that you are still friends. If things seem strange at first, don't worry and don't push to spend more time together than you are comfortable with. Accept that it will take time to recover from the strain on your friendship.