A very (and I mean very) colloquial way would be "Me tiene podrido/a", which is argentinian/uruguayan slang. It literally means that you're rotten but it refers to being incredibly fed up/done with someone/something. You can say it to people too ("¡Me tenés podrido!") and it can also mean you're bored/tired of something ("Me pudrí de estudiar, así que me voy al cine.")
If you wanna be very improper and rude you can also say "Que se vaya a cagar/a la mierda." (Literally "Go to shit", both as a verb and as a noun). You probably know these expressions can be used with people but you can also use them to refer to a situation you're done with ("No hago más este ejercicio de matemática, que se vaya a la mierda."). Following the same idea, you can also say "Lo mandé a la mierda" as a way to express that you were tired/fed up with something/someone and so you stopped paying attention to it/doing it ("La película era muy aburrida así que la mandé a la mierda."; "Mi hermana me tenía cansado, así que la mandé a cagar."). Remember all of these are very improper ways of talking, though.
Now for more proper examples:
- "Me cansé de esto."
- "Me harté."
- "No puedo más."
- "No doy más." (Argentinian/Uruguayan)
- "Ya no puedo."
- "Me tiene cansado."