My girlfriend is feeling lost in herself. She doesn’t know what is right or wrong, she feels like she lost her old self and wants to push everyone away so she doesn’t hurt them, including me. 
I have been in a spot like her before, and I don’t want to leave her alone to deal w this, I’m giving her space so I and our relationship do not exhaust her more, however I’m not disappearing fully as I know from my experience pushing everyone away will not solve everything. She is also young, 19 and I don’t want her to take the wrong path, I don’t want her to climb into substance abuse, relying on weed as a solution, none of that shit.
I personally was in the same spot, and therefor don’t want to leave her alone as I know it’s a hard ride and you can end up into deeper shit.
However, I do not know what to do exactly, I have spoken with her and I’m trying to lead her the right way, but giving her full control of it (herself), as I know you have to deal with this yourself to grow, but at the same time just pushing her away from fully destroying herself, but it just feels like I am doing nothing. 
If anyone has went thru this or had someone to this, let me know, as I don’t want to give up on us or let her destroy herself alone.