My heart is broken an confused advice please?

ok yesterday my boyfriend an i got into a huge arguement yesterday which caused me to cry an i made him bring me home. everything was going just fine until i walked into his room an saw him on fb sending females messages. i noticed he wanted me to see him doing that intentionally. it was as if he wanted to see my reaction. so i asked him what is he doing like are u serious. an he goes umm yea. im like wow thats disrespectful. an he says well i wanna have female friends im not trying to talk to them romantically or hang out with them i just wanna communicate. I kindly explain to him that i dont have a problem with that but at least u could have told me. so then he start snapping an yelling at me saying that i am not special an that he does love me but i will never be special to him. im like that doesnt make much sense. please explain an he says well the ring i bought u last yr was not no proposal it was a friendship ring an im like wow seriously? u proposed to me through a text. my mom saw the texts including his mother i kindly said to him. he goes well thats not what i meant im like ok watever take me home. so he brings me home then later i texted him telling him that i love him an i couldnt believe he said the horrible things to me. it hurt my feelings. he texted bak saying he loves me he just dont want to feel locked down an that he just wanna communicate with other women. 2 hours later he comes bak to get me we cuddle make love an fall asleep. idk if u were in my situation what would u do? we have been together for 3 years i am 22 he is 23. he just started college earlier this month an i will be starting in august i kinda figured he would start actin up a lil bit since he would start skool. i know that he loves me but im just so confused because he so loving an caring an romantic an tells me he loves me constantly but when he get caught doing minor things he blows up an says evil things to hurt my feelings to make me feel as if i am in the wrong when he is in the wrong. btw he seriously did propose to me through a text last october couple days later he bought me a diamond ring