Trying to find the strength to leave my cheating boyfriend 😞

Although he hasn’t cheated in a while and has worked very hard, he still continues to lie and manipulate. He lied again last night and contacted his ex and he knew what that meant for us. Although nothing happened and they didn’t see each other I am so done. He thinks I’m exaggerating cause nothing happened but I’ve been dealing with this for over a year now and I am just so tired. And after everything I do for him. He’s finishing his Masters with an unpaid internship so he lives with me and I pay all of his bills. While I understand he works hard and deserves some time out with his friends, I am not going to continue to pay for him to go out get drunk and contact other girls. Part of me feels bad because without me he can’t afford to continue his education. Not sure what to do