Firstly, there's no harm or shame in treating your hobby, for now, as learning to fly - it's not a race to a PPL.
Secondly, I agree with those who think that you should try and get some right hand seat time with friends who are going on trips. I suspect that you'll find that time spent in the air, with no pressure to perform, duplicating your friend's navigation, and also building up experience of being in the air - which makes a big difference to your free mental capacity to spend on tasks like navigation - will pay dividends.
Third - yes, there might be value in flying with a different instructor. I'm sure your instructor is good, but different people have different teaching styles and not every instructor suits every student. Somebody else might help you get the final issues cracked just because they teach it differently.
Fourth - don't give up. Flying's fun and there to be enjoyed. Other people (like my good friend Whirlybird above) have taken more hours to learn, and proved excellent pilots.
G