Similar thing happened to a friend of mine, he get enthusiastic about learning a programming language. He gets all the tutorials, books and every thing ready. He does it for next few weeks but after reading/completing at some point he looses the plot and life moves on. Then a few months latter he again begins the same cycle.
So what should he do?
My advice. Don't start again. This time when you get the urge to start. Don't take the tutorial route. Jump straight into the water.
Start by doing a project. Think about a project and begin it using the skills you want to build. Place a goal that you will complete the project and once complete, you will put the finished product in public domain.
This is a much better approach. Try it if you find yourself stuck in the never ending cycle of skills inertia.
Two clear advantage of this approach are you are creating something. And working on a project related to skills you want to develop, you will pick up more insight than just by doing the usual exercises and tutorials.
So if you want to learn catia, ansys or fortran. Try the project centric approach to skill building.
If you try this, please do let me know how you fared.