There will be a variety of opinions on this topic. Mine is: Someone you don’t know can’t bind you. For that matter, someone you do know can’t bind you. 
I’ve don’t often wade into the debates about “dark magic” but I strongly believe magic “against” someone will never work. Magic to control someone won’t work. Magic is pure. It is from the universe and it flows through us. We tap into it, not control it. And there is no way something pure and uncontrollable can be used for evil. Any anecdotal evidence to the contrary is likely coincidence.
But that is just my opinion. 
Editing in this: Others on here, maybe @BryWisteria for example, may have resources from the site to help with our struggles when stressed.