Why is my husband hurting my heart?

I have been with my husband for 4 years,and we got married last year in july. we wrote our own vowels and as we read them on our wedding day we both shed tears,he lost his mom and i lost my dad. through out the years we have been together,he has lied to me,he is talking to other women,they r calling his phone and he denies it and this has been going for years now. on christmas my husband went out of his way to surprise me with a diamond neclace and a card and he wrote in it. it says he is so glad that god blessed him with me. im confused i thought when u love someone u dont hurt them. i am a christian and i have stuck it out through the pain and tears, i believed god would change him, i am so scared right now,cause he looked me in my eyes and said im not in love with u anymore and he cant help the way his heart feel. and then today he said he love me and he wants to go back to church and let god handle it,so i agreed and now he says he is thinking that we should get a divorce,im so confused. those words that he said really hurt me to my soul,i have been faithful i have tried talking to him and as my tears hit the floor he looks at me and says he is not in love anymore,and when my phone rings he is always asking who i am talking to, i dont get it.i prayed and i prayed that he will love me again, but now im so scared that if he says he wants to try again my answer would be no now. what does that mean,y does the pain in my heart hurting me so badly. please give me some encouraging words and some honest advice.. thank u