I agree with you. Hitting the wall is very frustrating. I find that the only way to improve is to totally learn the song off by heart, then play it again and again until you can actually watch TV and still play it. In other words, the song or piece become second nature. The other thing is to accept that your family will HATE that tune by the time you know it as they would have heard it 1,000 times.
Lovely song by the way.