i invited my friend over all the time ,but she never invites me?

hi ,i'll try to keep this sorta short :]

okay so i have this friend ,lets call her ape so i'm having a hangout with a couple of other friends. there is friend A ,friend B ,friend C,and then ape . so me A,B are really close friends ,but C is closer to ape . i HAD to invite C because i thought that B,ape would ask C if she would come then she would probably ***** about it later on w.e .okay so i just went on vacation and was showing pics to all of them and ape didn't seem to care like when i show her a pic all she wouldsay is "cool" or she would raise her eyebrows at me or the pic (pic has nothing bad in it) we all went swimming and C ,ape started playing together and B,A were playing with me ,so i asked C if she could swim and she couldn't swim ,but she said she could so i brought her to the deep side and she started drowning so i helped her to safety.i invited C,ape but they never invite to hangout .B invited C,ape to hangout but im not invited and i just hate it when they talk about it in front of me its very annoying what should i do ? sorry for bad grammar i was trying to type fast