Unmotivated? You're a manager. I don't know if you know this, but being a manager is a very well respected position. Your friends who went onto being directors, are probably doing the exact same thing you are, but giving themselves a fancy name instead. Isn't a director basically a manager? You are doing everything right, it sounds like you're really just beating yourself up because you're not looking at the positives and only focusing on the negatives. I know it must be very difficult, working with depression is very hard. But the main thing to do is focus on gratitude, focus on what you do have going for you, what you already have, and the achievements you've already made.

You're a manager at 40? That's kind of a big deal. I know a lot of people in their 40s who would love that title. It takes some people a long time to reach a managerial position within a company. My mom is in her late 50s and she's an office manager at a university. You could look into other companies if this one is not making you happy. But you should really do little things to make yourself happy and calm at work. Because changing the environment doesn't always change the feelings. Don't be so hard on yourself. You're a success. It just depends on what you're focusing on and giving your energy to. I'm sorry to say this but at your position, it's really no one's job to make you feel like a success, that's all on you. You need to feel like a success within yourself, no one is going to remind you of that fact - in any job.

Even big shot lawyers, doctors, etc. don't have people helping them to remember they're successful, that's a very personal thing you need to grow yourself - because everyone is in the same boat as you, they might even be looking at you to remind them of their success and pat them on the back. You said everyone is an over-achiever, maybe they're just showing that to you so that they can get a raise or show off to the manager hoping you'll notice them so they can climb the corporate ladder.

By the way there's nothing wrong with having your interests shift. How boring would life be if you had one interest for a sum total of 60 years? Sounds like you just need to lighten up on yourself and give yourself more leeway, and focus on the little things that bring you joy every day. Interests are supposed to change, and there will be moments in life that don't interest you at all.