Devastated, dont know what to do!!? plz help!?

ok so, Billy and i have been together on and off (but mostly on) for the past year. hes 36 years old (I am 24), he has a good job but hes living in his parents basement right now. he has a 4 year old son and just went through a nasty divorce. it had nothing to do with me! we got together after the fact. i love him so much, we share soo much in common. his son loves me to death and we are very close. things with Bill got really good for a while, he wanted me to commit but i wanted to make sure things were going to stay good before i completely jumped in with both feet. but he adores me, told me i am "stunningly beautiful" and that he feels soo lucky to have such a catch and that he cant believe that he didnt see all my great qualities before, when things were rocky! i felt so good and excited. ive gotten into modeling and have been independent for over 5 years. but to my dismay, he started acting really distant out of nowhere about 2 weeks ago. he wasnt really saying i love you and just didnt seem as into me. he randomly started giving me this BS that he didnt want to be committed, and wanted to be able to see other people! ouch! it devatstated me, how do you just change that fast!!? i went to go visit my mom in florida last week. i was only there for 6 days! he didnt even call me once while i was away and didnt even return the 3 calls i made to him. it ruined my trip cuz i was so upset and confused. he did come to pick me up from the airport this saturday with his son, he ended up telling me after i asked what was going on and he told me he met someone else. and that its not serious with her and he doesnt want to be committed to her (or anyone) he said he doesnt know what he wants right now. i cried but i didnt beg or freak out and i havent called or seen him since he carried my suitcase upstairs to my place and said im sorry, gave me a long hug (that i didnt return) and said be strong please! then he left. since then no word!! its killing me!! but i will NOT call him and be rejected and look pathetic and desperate. i dont want to push him away further! but i want him to realize what a huge mistake this is and come back to me like he was before. what should i do!? i dont want to totally give up either! :( thanks guys!