I obviously can't do this, and I was hoping by moving to a programming language other than GML, I would have more options and opportunities to choose from. I've been making games since 2003, since then I've became a more skilled programmer in GML, but like I mentioned above...I don't really know if anything can help me achieve my goal.
It does sound like you've gone far enough with GML to know what you're talking about. There's a few things which spring to mind here as options...
1) You could try writing some stuff using C#, most likely using Microsoft's XNA system. C# is much less wild and woolly than C++ and will behave itself while you get on with making games.
2) You could have another try at C++. If you're serious about writing
good 3D games you have to realise that learning C++ is the least of the obstacles you'll face. Most probably you're more than capable of learning it if you're patient.
3) Try modding an existing 3D game. This is a great way to learn stuff and has the advantage that you'll see results early, which may keep you motivated a bit more.
[Disclaimer: 3D isn't really my area of expertise - I might have missed better options]