I hope you will agree that age is secondary to your happiness, at what point you can best cherish whatever circle best fits you. Life takes its own path in what it puts on our plate but being yourself will only draw others towards you. Being a good genuine soul often wins over many of the social anxiety dreads. As many will say, stay the course and be true to the person you choose to be. Perhaps I'm all over the board, but still wishing you a special day.

We all have a desire to feel connected to each other, in some way and I know I have nothing in common with some of my friends but I am willing to listen to them and be kind to them because I accept that most of us are different and that's what makes us unique.

https://www.youtube.com/watch?v=HGqw6kcrdDk&ab_channel=MGAcademy-TheBenefitofknowledge

As my2centz stated, age really has nothing to do with how large your circle of friends should be. I think that your situation might have an extra complication. It sounds like you may be looking for a smaller set of really good friends that you can count on to be there while your fiancee is looking for a larger group that he can hang out with. My guess is that it is compounded by the fact that your group has been shrinking due to circumstances beyond your control. You then look at other people in your life (his friends) and realize that none of them would make the cut for your group and it is even more depressing.
If you have concerns about his friends using him, I would discuss it with him. See what need these people are fulfilling for him that he is willing to overlook or accept what they take from him.
As for meeting new friends yourself, I think you first need to decide what needs you have that you need them to fulfill. Can your friend that moved away still fill part of them through phone calls and video chats? Do you need someone there in person? Can you and your fiancee fulfill each other's needs without bringing in so many outside people? How does interacting with people on sites like this help? There are so many options but only you know what will work for you.
The key is to be true to what you need. You can't base it on your partner's needs or you will never be happy. Give yourself time. This has been a really messed up year and everyone is trying to figure out what normal should look like now. Your feelings are not only understandable but normal. In the end you got this but if you ever feel you don't you can message me. Prayers and Love.

well, you're being social now just in a different way. i don't know how many friends one should have in their circle at any age. but with this pandemic it's a little difficult to control you know?

i'm not used to having any friends so there's that. finding others to talk to online is a treat for me. :o)

if your fiance's friends are shady maybe ask him about them?

hope you feel better soon.

There's no set amount of friends for any age group, although I think as one gets to be your age, they find their circle of friends generally shrinks. People start putting more time into improving their own lives, marriages and careers and have less energy for socializing. They also find that a few good quality friends are better than many meaningless relationships. A good way to meet people is to volunteer or join a club where you can spend time with other people with similar interests. This can be done online, as well.

It depends on lifestyle. Because of the works i do, i do not have a circle of friends. I make friends when i can, and if i need to. When you are 30, its hard to make friends because that is a very awkward age to have friends. We are too young to hang with 40 year olds and too old to hang with teenagers or young adults. I guess the best option is social media for the time being.