Buy a book called The Complete Guitarist by Ralph Denyer (if you can still get it) - go to the section on scales and start learning the major and minor scales in all keys - then improvise over a piece of music you know - add little notes and run up and down the scales. It takes time but it will eventually unlock the neck for you and you will get to a point where eventually you don't even have to think about it. Someone, many moons ago, prescribed this for me when I was struggling with learning the guitar. It works. Once you have learned the scales you can abandon them and do whatever you want. In order to get to the top of the mountain you have to walk through the valley first. There's no shortcut to good musicianship. It takes work.
'The purpose of life is a life of purpose' - Athena Orchard.