I am an introvert.
I don't live near my family.
I've lived in several cities of varying sizes during my adult life.
But, I don't feel marginalized. I think it's because of two things. The first is that my nuclear family growing up did not live near much extended family. My maternal side of the family lived on the opposite coast, I saw them every 5 years. So, I did not grow up with an expectation of having my parents/siblings nearby as an adult. Since I didn't have this expectation, it doesn't bother me that they are not physically close to me (I am still emotionally close with them).
The second is that I have joined a few groups that make me interact with others locally. I joined a book club and a local women's group (check your local library for groups like this). The local bowling alley is also advertising looking for women for their league - I might join (I am a terrible bowler, but the ad says it doesn't matter and it looks like a great way to meet people without pressure). As an introvert, it would be VERY easy for me to stay inside of myself, on the couch with a book by myself, most of the time. These groups (plus my job) provide social interaction for me and the casual friendships that I know that I need, even though it's not easy for me to make those friendships on my own.
I really REALLY encourage you to find a group that looks interesting to you and join it so that you can feel more connected to your community. It could be a book club, bowling league, running group, dinner group, chess club, volunteer at the local food bank, walk dogs at the local animal shelter. If you don't have a job, you might get one even if your family doesn't 'need' for you to work - maybe part time in a small shop nearby. It doesn't really matter what the activity is - it's the connections to your community that you need.
Good luck.