I Hate When People Assume Things

i really hate ppl doing whatevr they want n saying "m sorry, i assumed"..a few days back, i was outta my classroom for some work n when i return, i find my desk occupied by 2 assholes n my bag no where in sight..i found my bag at the last bench n when i asked the 2 guys in my place..they were like "we're sorry, we assumed u wanna sit wid other girls at the back.." cmmon..first the whole grade knows that i nevr evn look at the girls who were at the back..plus, the know i dont like ppl fiddling wid my things, specially my schoolbag..n evn if they didnt, who the hell gave them the right 2 assume things about me?!?!u can assume only when u know a person inside out, when u know exactly the way they think, n exactly what they're gonna do..they barely know me..i ws really irritated by this,..n its not just once..they always do the same n expect me 2 settle for a "we assumed"