Answering all your questions in sequence.
I like to code to an extent that we can call it love. (But learning curve of a new tech makes me impatient sometimes)
Yes, upskilling is important, I like to do so every 2-3 months.
I started liking coding because first, good money obviously, and if you are in a start up or smaller org, your work has visible effect in terms of operation/performance which translates to real money. Having a skill that makes money, that too on a scale of millions feels great.
There are days when I don’t like what I do, there are even weeks when it happens regularly, I think the best at that time is to talk to your superiors about the burn out, change or switch tasks or even take a short break.
Constant burnout will make you hate everything, not just work, even personal relationships.
If you even slightly like to code or are fascinated by it, this is a beautiful industry I believe, but factors like bad managers, bad org, bad wlb, affects our impression a lot. Don’t hate the game, just avoid or quickly move on from bad players