How does an adult go about making friends with other adults?

My fiancée and I moved here about 4 months ago. I love it and him so much but the lack of friends and family has really been making me sad. I work in an area where people sit outside to eat lunch and I always see girlfriends out together and families and it makes me so sad. I’ve been reading so much to keep dismissing the fact I’m lacking. And it’s not that I want to replace my friends who live in another state so it makes me feel guilty. I guess I’m not really sure what to do. I eat alone and do things all the time but sometimes it’s the worst and it takes all I have to not start crying lol.