You are describing the hedonic treadmill. Essentially, you become used to your surroundings, and while they are objectively great, from the perspective of inside your own head, this is now normal and you / your monkey mind wants more. There have been a lot of post floating around the internet with various solutions, the most popular being Stoicism > Positive Psychology / Happiness research > Buddhism / Meditation. I'…
1. Backpacking for a 1 week time period or longer. Living out of a backpack is a great way to help rest your brain terms of its standard perspective on what it thinks it needs to be happy in day to day life. Also, there are some nice places you can walk to with a backpack on that you can not drive to.
2. A Therapeutic mushroom trip - read how to change your mind by that hippy Berkley professor. This is not for everyone though. So proceed with caution.