Can my exhusband keep my kids from me when we have 50/50 custody

I had to live with my ex because of my situation, we have 2 kids together. He has been telling me to leave for a long time now because i dont want to be in a relationship with him. He works i stayed at house took care of kids etc, finally he told me to leave again and i did cause i couldnt take it anymore, my kids knew where i was going and why. Now he will not let me see my kids or have them on my time because i left and he supported them and i just stayed home and took care of them. I dont have money to fight him and he has his parents who have all the money in the world and they are watching my kids. What can i do i love my kids more then anything and he told me to leave and i just want to go on with my life