Hi praying. Don't "ask" him to call before he comes over to use YOUR home as his gym. He is STILL cake eating here. He wouldn't just walk in a friends home without so much as is this a good time. He can do his laundry at his home, workout at his home. What would happen if you decided to store some of your stuff at his brothers rental and came and went as you pleased? Might cramp his dating plans!
Tell him to get his weights out of there or join a gym. He can't think of anyone but himself right now, that is clear. If he wants to act like a jerk he has to pay the consequences. Until than, why change what he is doing?
Hang in there. You're getting stronger and it can be seen in your posts. The best thing you can do now is get your a your kids life's together. Learn to live without him and do well. Teach your kids that strong people keep their promises and responsibilities. Show them the RIGHT way to be an adult. You can do this. Stay strong!
