Why are you trying to all, text and email him all the time? He's right, you aren't respecting his space. Leave him alone and move on with your life and let him move on with his. You'll know you've officially done so when you stop feeling the need to be in contact with him constantly. You are NOT going to be able to be 'friends' at this point in time, especially if you start obsessing over him seeing other women. It doesn't matter at all how long you were together, you've broken up.
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mohandas Gandhi