Should i stay or should i go?

I have been with my bf for 7 years. we have three kids together and he has two from a previous relationship. I feel like it is past due time to get married. he won't commit to it and says hes just not sure. that is a big concern for me mainly because after all this time he still doesnt know if im "the one". also, he continues to talk to his ex (daughters' mom) off and on. I dont mean romantically, but just casually for long periods of time. She has tried to break us up since the very first day so i feel completely disrespected that he carry on a friendship with her. Ive told him how i feel and he always says he will not talk to her about anything but the kids from now on but always ends up have a day (like yesterday) when he talked to her for 45 minutes when he was walking the dog. i dont know what to do. LIke i said, we have a family, home, life together but this is only half of the relationship i want with the man i love. I want him to be crazy about me as i am about him and i want the same respect i show him. Should we take time apart, should i wait it out, PLEASE PLEASE HELP! its everyday torture feeling like im not enough for him. thanks in advance for your advice