Garry's Mod Start up problem(HELP!)

Hello, My name is Greg, I bought Garry’s Mod about a year ago, it has been working fine. Today I thought I would play it but something weird happened.
As I started it up it loaded and then showed the guy with the Phys gun’s back. As the blue loader bar came up on the bottom, it would stop on
“Initializing Serverside” then the screen goes black and doesnt respond. PLEASE HELP!

-Greg

PS: I have the -dxlevel in the startup so it cant be that.
PSS: It does this with all Steam games.

PC specs? somehow i doubt it’s that though might aswell
have you tried reinstalling steam?

Yes, I have reinstalled Steam, twice actually. I even reinstalled Gmod. My friend already did System specs, he got nothing.

That’s EXACTLY what mine does…I just bought the game, and it hasn’t worked once! I’ve been waiting to buy this game for about 3 years, and now it won’t even start…someone please help!
And yes, I tried -dxlevel 80, 81, 90, 8, and 9.