You will find great joy and happiness if you can overcome the inertia, get up, and be active on a daily basis.
If you stand aside and watch the world go by, you will be left behind!
It doesn't matter what you do: join a gym, a book club, a church group, a volunteer soup kitchen. Or try something you've always been curious about: a photography or scrapbooking class, or free lectures at a local museum. The point is to get out and mingle, to take advantage of the endless riches life throws in our path every day.
There are many benefits to active participation: a sense of belonging, a physical feeling of euphoria and well-being, reduced appetite, better moods. Not to mention new friends who share your interests.
Now...stop thinking about being active, and be active! Making the slightest effort will reward you handsomely.