Life Threatened by roommate, legally can the lease be broken?

My mother lives in a 55+ community, and made what she thought was a good friend, they spent all their time together, going to church, and life groups together, but as friends. When it was time to renew their leases, both were up at the same time, they decided to move into a two bedroom two bath place, they would both have their own room and bathroom, but as soon as they did, things took a turn for the worse. He expected more from the relationship, and my mom, who is in recovery for alcholism relasped in an effort to push him away. Last night he threatened to kill her. Can she break the lease and kick him out, or move out herself? I can't let her stay their under these conditions, she is trying to sober up, with someone threatening her life in the other room!