It's sweet that you don't want to hurt them but how you spend your time and attention is YOUR choice.

It was sweet of you to take the time to reassure them and not be critical but since you haven't known them that long, it is OK not to respond. That is a message in and of itself. As Happycrafter said, they are probably struggling in some way but messaging someone back all of the time should not be something you have to do. If you have time and are in the mood, then fine.

I agree that they probably latched on because you are kind/caring/etc. plus maybe they thought they have something in common with you. I have been guilty of feeling like I "know" people after reading lots of their posts. When people have some sort of disorder/are in crisis (you can only do so much when someone is in crisis--don't let a stranger manipulate your time because you can only help so much), they don't act "normal". If the messages aren't' mean or threatening, I think it is OK just to ignore them if you aren't comfortable. You obviously aren't the type of person who treats anyone harshly. So I vote ignore (not an ignore button but, just don't open the messages). Sometimes when I message people, I get something out of just composing that message (sort of like journalling) even if they weren't read!!!

Oh and Dear Sweet Fuzzy whom I sincerely like--sometimes wanting to be liked (overly concerned about offending) and feeling a constant obligation to serve others or stop them from hurting (we can't ) can be a bit disordered in and of itself (I say this as someone who does this to some degree).