At some point you will realize that you have done too much
for someone or something, that the only next possible step to 
do is to stop. Leave them alone. Walk away. It’s not like your’re giving up,
and it’s not like you shouldn’t try.  It’s just that you have to draw the line of determination from desperation. What is truly yours would eventually be yours, and what is not, no matter how hard you try, will never be.