He makes me cry every other day....?

I am head over heels in love with my man - he's a bit like that sonnet- when he's good he's very good, but when he's bad, he's wicked - when he wants to, he can fill my love tank to overflow - but at least once or twice a week he has me in tears because he's let me down in some way. My family and friends keep on telling me to not have any expectations. That I've made him too secure in the relationship. I don't want to have to live a lie. I love him. I know he loves me. But I don't know if I can take all the heartache he gives me though. The good and bad are pretty even stevens at the moment.......when he's mean to me I am always shocked with disbelief that he could treat me so badly. But I always forgive him. Because I love him. When do you know that it is time to move on? Do you think he is ever going to be able to treat me with respect in the way I deserve?