Dear me, 

You shouldn't have wasted your time with him. 
You shouldn't have spent a lot of time with him.
You shouldn't have fallen in love with him. 
You shouldn't have said things you didn't feel.
You shouldn't have kissed him. That was your biggest mistake. 
You shouldn't have cried so many times because of him.
You shouldn't have felt guilty because of him. 
You shouldn't have let him play with your feelings. 
You shouldn't have told him everything was okay.

You shouldn't have... but you did. 

But, are we talking about just one guy or... two?