vent about friends

I don't how to describe my friends, there are times where i feel like i wouldn't trade anything in this world for them but there are times where im in their presence but i feel left out. i feel like they're just using me for their needs. like there's this recent thing, we have exams and I unluckily got cought cheating on my test and they ignored me?? like how that affects them? it's not like I haven't done this, i've done worse , they just never know it.