Gnome doesn't want start

my problem is following: some time I just restarted my computer, after restart the gnome doesn't want to show up, I have only the 6 tyy's terminals ( I can log in and do whatever I want ). I am strugling from yesterday why is that when I type:

service gdm3 status

gdm3.service - LSB: GNOME Display Manager
Loaded: loaded (/etc/init.d/gdm3)
Active: active(exited) since Fri 2015-01-09 13:57:38 CET; 2s ago
Process: 995 ExecStart=/etc/init.d/gdm3 start (code=exited, status=0/SUCCESS)

My distribution is Debian jessie(testing), but I have tried to downgrade it to wheezy ( I though that maybe some recent update of jessie caused the problem), but after downgrading the problem still exists. SO right now the state of my Debian is wheezy (stable). Please for help because I can move on. Show me some instruction because I got stuck and don't even know where to look for the problem.