My guy friend tries to post personal things about me on facebook?

I don't really know him I just know his sister. I text him a lot so he knows some things about me. He is one of the only ones who knows about my depression (I told him that because he was feeling depressed and knowing he's not alone made him feel better). I have "major depression" but his depression is just feeling sad when something bad happens. Anyways one day I checked comments on my facebook page and he almost revealed my depression. I ended up deleting the post he was commenting on to try to stop him. It worked but i'm scared of what he is sharing so carelessly. What should I do?