This is a very slippery slope. You are describing a new relationship but defining it by not having sex, no commitment, etc. I am afraid that you are convincing yourself that this is a friendship when he is actually treating you like a girlfriend. I want you to be aware that he could either be keeping both doors open (you and her) while playing both sides or know he's playing both sides. It is still early and you may do well to let it go. He could hurt your feelings if not. You could also see where it goes but keep in mind you could be wasting your time and setting yourself up for heartache. I would in this case keep contact to a minimum not several times a day. That way you protect yourself from getting in too deep.
If he is certain that he is going to date this woman then he is saying that's where his heart is. The most you can hope for is picking up the pieces. I would decrease my contact and availability until he is done with woman two.