how close is close

My boyfriend’s friend is constantly blowing up his phone and always at his house, he will answer his texts on a dime but definitely not mine. And tonight his friend has been at his house past midnight and for what reason? My boyfriends parents are out of town too, like I just don’t get it cause he stopped telling me that he even hangs out at his house with him and I don’t like it:) anyways, just venting.