Why does every other site state that the song starts like “I refuse to abuse what is kind to the muse“ when clearly Greg sings „kind to diffuse“?

I think "Tommy" is the character from the rock opera by The Who. I don't remember much about it, but I think when his actual and metaphorical mirrors are smashed, Tommy can see (he was deaf, dumb, and blind), and is finally free.

This would also be consistent with The Who's song, called "I'm Free" (I'm Free, and I'm waiting for you to follow me), on the path along the way.

It seems really obvious to me, that this means that you should forget the thought of becoming happy and loving someone because you will lose the things and people you love along the way - unless you are able to stay strong when they are finally gone.

What I find to be interesting about "Along The Way" is that I often read it was about suicide, probably because of the line "like Tommy, you are free". But that song was written in 1984, and Tom Clement died in 1986. So I'm really wondering who Tommy is in that case, and if it's about Tom Clement, what made him so free. Apart from that, the song seems to talk about life, how you lose or rather change your ideals, views and friends, but in the end it's still a part of you and your life and makes you who you are. The second verse in general is about old friends chosing a different path in life, while in the third verse, it becomes clear that your past is a part of you and eventually you will face it and the things of your past again, along the way - where the "way" is just "life" I guess.
And could "But forget, don't regret, to find love and happiness
Unless you're willing to be strong when they are gone along the way." be a typical Greg-statement on responsibilty, in the vein of Kant? 'Cause if you just push away all the doubts and bad thoughts, you might be able to be happy, but in the end, this lack of thoughts and substance is destined to perish and will leave you with nothing once you're on your own.

'I refuse to abuse what is kind to the muse.' Could this possibly mean drugs? Certain drugs, particularly marijuana and opium, are associates by many people with insightful and creative thinking. A little joke, perhaps?

I think this song is about how if you keep trying, and you keep putting up with any hardships, the reward will come eventually.