what should i do this guy likes me but i don't like him?

well here is the story there is this guy that is much older then me , i am 33 and he is 48 and i don't like older men i have always dated younger men why ? who knows just me well he like me have brought me a ring tell me he loves me and want to marry me and get a trailer together , well i got a bf that lives in south carolina i have being seeing for 9 months now that i am in love with very much , that i talk to every nite , well this other guy have brought me a phone too , give me anything i want , well i don;t want him and have tryed to tell him and he know that i got a bf but he stay paying me things and come over my house at 5:30am to go to bed , i am really getting tried of him coming over there everyday and staying under my butt all the time . rubbing on me and calling me baby , oh he is nasty too he **** on hisself too a very nasty man , don't take a shower . so myh question how can i tell him in a nice way that i don't want to be with him that i just want to be his friend . please help