why did my friend lie?

so i asked my friend ''how are you doing?'' she said good I said ''frfr'' she said ''yes im good'' i said ''ok'' Then she posed a picture saying ''i wanna kill myself i told my mom and she said it was hormonal i really wanna kill myself"' under it so i asked again ''how are u'' and she said 'good' so I said ''im sorry for every thing"" and alot of other stuff and asked again she repeatedly said good so i brought up the picture then she actually told me she felt horrible but avoided talking about it way wouldn't she tell me what was wrong? when i said ''we shouldn't talk im making your life worse'' she said ''you stopped me from killing my self'' so if she thinks that why wouldn't she tell me what was wrong? i really care about her idk what to do she could be hiding alot of things...