I've was with my Ex Girlfriend for 6years we spent all our time together had two lovely children but recently things have turned sour and we have split up I'm 27 and now living back at my mums in the box room. I left her everything we owned in our rented house the car and most important of all I won't be seeing my two children as much.
I still love my ex and I've tried to get her back but she's said no and says she means it I'm distraught about what's happened can't eat sleep or think about anything else.
Where the hell do I turn to from here

I would suggest NC, but there are children involved so I do not believe that would be best. Time is the only thing that will help. If you want to see your children more, file for joint custody in court. Have contact with her only when dealing with the children

I suggest that if you have not done so already, STOP, stop doing things giving away your rights and your property, it is not going to do anything but hurt you more.

You get an attorney today if you don't have one. You file for joint custody so that you get the kids 1/2 of the time.
You have to stop playing nice and fight like a dog for the sake of the kids and your relationship with them.

She will use "love" and hope to drag you into the worst deal where you seldom see the kids if you let her.

I would hope after your heartache is under control, you work with your baby mama and be a great DAD! If you cannot work together in the best interest of the kids... the court is the best course of action.