Is it heavy or am I wimpy?

I just got two new things and now my camera is REALLY heavy to me.
I'm having a hard time holding onto the thing.

I use the Canon 5D with smaller primes usually.
However I just got a 580 EX II
and just got the Canon 24-70 2.8 L
I have the extra battery grip and the nice high end wrist strap.
Neither reduces the weight or strain though.
This lens and flash on the camera are really heavy for me.
I'm just amazed the massive weight difference over any of my primes and this 24-70 2.8 L

I'm seriously thinking about returning the lens to the local shop in trade for another prime like the 80 1.2L or 50 1.2L.
The IQ of this zoom is great for a zoom, but I’m not convinced I’m totally happy with it over any of my primes.
Which makes me want to shelf it and just use a prime, at that end I should return it though.
Maybe I just need a new Gym membership, but I have very small hands and forearms which never got much better with exercise.
Maybe I just want an excuse to not like it and so I can go for the 80L prime. Lol
Then I just looked up the 80L weighs slightly more then this 24-70 L oh no.

Any thoughts from the DP community?

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-Steve