IM 13 and feel like a big loner!?

I used to be part of this real tight group but know i am always home by myself with nothing to do. I have this friend since 4th grade all we ever did was hang we were like brothers now we are in 8th grade and we talk and mess around in school but after school i feel like he doesn't want to be around me he always says lets hang on the weekend and he always says he can't last minute and then 10 minutes later he is hanging out with everybody else. I get along great with every one of my friends but i don't hang with them after school or on the weekends anymore. I feel like a loser and i am embarr cause my dad is know always seeing my mope around the house and im partially pissed at my dad cause he is very overprotective ever since my mother died and doesn't let me go most places by myself so i can't hang at the mall with my friends he says there haves to be a parent but no one wants there parents at the mall with them and their friends. That kind of keeps me from having people over at my house cause then we would be bored and my dad wouldn't let us go out some where and then they would call me a loser or something. What do i do! How do i get my best friend to start hanging out with me again. I feel like a loner