The thrill is gone?
We could be twins.
My passion got superseded by a new one, namely, the Word of God. It started in about year 2000. By 2015, I had got a bunch of understanding that rapidly led to my current status.
I just turned 71, and I can't see this passion ever waning.........
Make that triplets.
Like the OP, I had the Matchboxes and Hot Wheels [ still have them all ] and played with them all the time. Drew cars. Read every magazine I could get my hands on. Bought my own first Hot Rod magazine with my own allowance at the age of 5 . [still have it too] The fourth intelligible word I uttered was 'car'. Only continued to breathe so I could get that drivers license. Once I did, went to every race and show in a hundred mile radius for years. Once a little older, went to them all over the country. At one time subscribed to 17 motoring magazines. Worked in a parts store. Made the mistake of taking a job in a 'profession' [cough cough] tangentially related to the auto industry out of college and got stuck there for ~35 years. Cars [and motorcycles] have basically been the majority of my whole existence.
Now, I hate to hafta work on them. Don't go to very many events; there is a fairly sizeable one coming this weekend about 25 miles from my house and I doubt I will find it worth fighting the people, traffic etc to go. Hold it - just hit me; there are TWO decent sized events close by. Probably won't hit either. Definitely burned out and no , you're not alone. And no, I dont think its temporary. [for a multitude of reasons/factors] But back away for awhile and maybe the pilot will re-light.
Personally, Ive always been pretty passionate about the Word of God, but i find it growing as I grow older. Maybe that comes with age, maybe maturity [maturity?!?!?!?!? OH NO! Say it aint so!] But Im right there with ya.
I have found that my interests in things automotive [and motorcycle] related is stronger now than the cars themselves; show me a bunch of old gas station signs, books and brochures, art or old toys and Im still pretty much there...
But hang in there OP, you aint done yet. And youre not alone. The intensity may wane, but I imagine you'll still get some stuff done occasionally and enjoy it some too. maybe just not as much or as intensely as before.