Im sorry but it sounds like he is just using you for the sex without the marriage bit. Dont have him come to your house nor do you go to his house to have sex and YOUR CHILDREN see that you stay at his place and vice versa. You are already screwing up the thinking of your children in what is right or wrong in how families should be.

Dont chase after a man nor listen to friends. You find out yourself what is going on with him. If he is only calling back when he feels like it then you are not important to him (until he needs sex or companionship) and that is not right. Friends are there for each other. No excuses.

OH~ and you do not owe him sex for anything. Making him wait for sex HAHAHAHAHA PLEASE! What has he done to deserve sex with you? If he has not promised to marry you and take care of your kids and take care of your emotional needs..he does not deserve sex from you at all. Dont give yourself to the random man. You want one tht will take care of you, your children and your needs while you do the same through MARRIAGE for him. Yall wont die without sex. You'll be alright.