Of course you can. What makes you think you can't? 40's is still young by many standards. It all comes down to one thing and I'm pretty sure you know what that is. Practice, Practice and yes more Practice. I know that work, family, home maintenance can get in the way with all that, but if it's that important to you keep doing what your doing and it will get there little by little.

The bigger question is if you don't become the guitar player you want to be, is that really such a problem? Look at it this way. How would you answer the following question to yourself 2 years ago.

Is it possible to learn guitar at 40-plus?

Well I think you know the answer already.

Enjoy your journey and don't focus too much on where it takes you.

Moe