>If you want more money look at where you can save money (not eating out, buying generic products, etc.) and things you might be able to do on the side to earn more.
Oh dear god, the guy is depressed and now he has to stop buying his daily coffee too? And possibly a second job!?? You're an engineer, not a tollbooth operator. You're in one of the few fields that's actually growing and still pays worth a shit.
On the money front, take several queues from Ramit Sethi. Level up, do a cool side project with the latest React/Vue/Node and learn a bit about selling yourself.
Most engineers, even if they're really good, decide to take the humble, quiet route and demand a "fair pay". It's bullshit, it's a cop out, and if you're just 10% confident, you can increase your next jobs's salary with the money the other introverted engineers left on the table for you.
I mentioned that first because it's easy to fall into a lifestyle trap and think the only way to cope is to get a job that makes more. The formula for money is income minus expenses, so you always have two variables you can play with.
It also makes a nice mental segue for people into the topic of getting a new job, a topic which people can be adverse to. It creates a choice that seemingly wasn't there before.
FWIW I wouldn't be so quick to turn your nose up at side gigs.
I have a friend who picked up an old vinyl decal cutter and now makes a significant amount of his income by selling custom decal stickers for cars and windows and such to local businesses.
Similarly my neighbor does lawn aerating in the spring and sprinkler blowouts in the fall and considers it a refreshing break from his work as a PM.
The money wasn't prior number 1 for me, so probably it's not about the money.
What is really matters for me are people that surrounding me every day when I come to office.
Recently, we've been merged with another team. We where doing a great job before, a team spirit was so great that we where able to deliver better than others.
I literully was waking up with a huge smile on my face, because I knew that today we gonna do some awesome shit (no matter if it is bug fixing or performance improvements or new features).
Now, we have super huge team tons of projects and instead of goals that we are desire to achieve we have tasks that we have to close.
Now, I waking up with a sad face, because I know that today I'm going to "close the next issue", instead of "work on chalanging problem" that makes everyone in a team to feel proud of that.
Close the next issue ... in life ... and change jobs. Explain to the management why you're doing it first.
In order to fix that I think the advice of "discipline" as mentioned in another comment below, is key.
I have so many goals on so many topics that I can't work on all of them every day. However, I started with one (exercise), and worked to be disciplined on that one, dedicating 1 1/2 hours, 6 days a week. I also added meditation (I practice buddhism) for 1/2 hour every day, where I clear my mind and focus on all of my goals.
After consolidating exercise and meditation, and feeling that it was already part of my routine, I added a second goal (studying). All of this while having a 9 to 5 day job, remember. I leveraged on apps for reminders, and habit trackers so I try not to "break the chain".
I went from being quite unmotivated, to being motivated on different areas, and that pushed me to find ways to be motivated at work.
Discipline goes a long way.
It's very clean and flexible.
If you want more money look at where you can save money (not eating out, buying generic products, etc.) and things you might be able to do on the side to earn more.
Or if you rather start applying for jobs and seeing what else is out there. You don't have to find a job today, just start looking.
If you want to have more energy find an exercise routine that works for you and start eating more vegetables and less sugar/bread. Take time to meditate or at least relax and clear your head. It's likely there's something buried in your head that is causing you to be demotivated.
If it's your perspective that needs tuning work on rewiring your brain. Stuff like replacing "this is hard" with "this will take time" or learning to be okay with being wrong/weak and asking for help when you need it.
If your work isn't fulfilling maybe talk with your co-workers or supervisor to see what can be done to make it better. If that's not realistic, maybe your job actually does suck and you need to go back to the first paragraph.
For me personally, I find setting aside time to untangle my brain helps the most. Sitting someplace and working on a posture or breathing exercise and really just putting some distance between me and my problems for a little while.
Usually after that my problems seem much smaller and more manageable.