((((Calista+12))))))))))))) Im so sorry that happened to you. No you were not stupid. You were trusting. It is very true about being careful who you trust. As i learned that lesson the hard way. Which is why I am seemingly preaching about this.
You are so very right it can be harmful and dangerous.
As always my adise is do not give out your phone #. e mail. address. real name ,. unless you are very sure about the person. If something does happen keep all records of it and block that person right away. and notify the police.
No one has the right to do that to another .
Take care of you and be safe kind one.