Why do people want to __HACK__ other peoples accounts ?

Things like Hotmail , Facebook etc…..
I had someone ask me the otherday , if it could be done and how to go about doing it . I said lots of so called hacks are fake , scams and or virus to use them is a risk you have to think about .
When asked why she wanted to hack these accounts she said , “Cause i don’t trust him , we just got back together and he is acting coy with me . I want to find out what he is doing !!!!”
My response was if thats the case whyare you still with him ?
No reply :

Now al i get is help me hack it , can you direct me to hacking it . I just sent a link to a random google search result and said follow the instructions .

But why hack the account to get the information , why not just ASK the person whats going on . Ok you may not get a response , tough shit what they do is up to them if you think something is up ask or leave . Surely that would be a more grown up way to do something