Is his bff offended...or does he not like me?

Me n my bf have been dating for 4months n ever since his bff n his gf broke up hes been on us like 24/7. Like weve had 1 fight n the other small arguements every once in a while r from his bff. Ive nvr done ne thing to piss him off ive been nice to him hes cool kid. but i feel lik part of him doesnt want us 2last which is hard bc my bf just told me he loved me n has never felt this way b4. His bff texted me from his own fone (bc my bf has no texting) sayin it was dustin hi i miss u....then lik told me 2sut his dit? n i said no rude. he said we bweak up then i said k bye. at this pt i fig. it wasnt him n he basically admitted it wasnt my bf. so idk wat to do or say 2him?bc my bf says his bff likes me n has no problems????!!!!