My bf didn't stand up for me at school and it was serious?

Okay so me and my bf are both 16 and in the 11th grade and we have been dating for a year and a half...sooo today after lunch we were walking in the hall and he saw his friend and he slammed really hard into my bf on purpose knowing I was next to him and so my bf fell into me and I almost fell over!!! Soo I went up to his friend and said WTF don't push into my bf and then almost knock me over ! And then his friend goes like shut up or I will light your *** on fire and took out a lighter when no teachers were around opened it and tried waving it near my clothes and chest area but there was no flame coming out...and my bf is just standing there not doing anything so I go like WTF you didn't even stand up for me or anything and I was in danger, he said why are u getting all mad for your acting like a jerk too meee and I go like your the jerky one and he said whatever fine then dont talk to me and I said ok fine I won't...then after cl he shows up outside of my clroom and then walked me to my cl and I gave him a long hug...then he texted me saying are u going to be happy now and I said are u gonna stand up for me now and he said idk then I put wowww and he said look babe I just can't so stuff like that Thats why I'm joining the military to be more tough maybe but idk ok? Then he put next time i'll do better ugh what do I do?