Hello, please do not give into sadness, which loneliness can lead you toward. Although not a sin per se, it makes us vulnerable to fall into depression or excessive sadness which Satan loves to prey upon. We are then more likely to mortally sin.
God realized we needed companionship (“It is not good for the man to be alone” Genesis 2:18)
Although I am also not a social phenomenon but have a group of friends who frequently see each other.
Finding a good friend is indeed a great blessing, however we must we wise with our friendships. Good friendships should bring us closer to God and bad friendships do the opposite.
For me, a great way to expand my social group was Bible Study group at the local parish (although other voluntary activities or evangelization could also work out for you). We all love Sacred Scripture and enjoy debating and understanding difficult passages of the Bible.
Often we also share our problems and concerns (as much or as little as we each feel comfortable to do so) and others give their opinion and knowledge so we all feel more connected and supported. Plus you get great ideas on how to approach a specific problem.
One thing the Church excels at is bringing people together, rather than dividing them apart.
Most of the saints I have read seemed to be very social people, partly because of the miracles attributed to them, their joyfulness, amazing sermons and charity when dealing with others. Although some of them decided to become hermit and some religious people decide to stop living for the “world”. They still interact with other people and each other as a community.
After all we cannot do charity and practice other virtues if we are completely alone. Having God also brings great joy and prevents us from feeling lonely.
Many saints warned us not to give in to sadness, but on the contrary encouraged us to be joyful.
One man found the secret of true happiness. His name was St. John Bosco. He was a man who experienced many trials, but who also lived a life full of gladness and joy. St. John Bosco was so happy that he could hardly contain it. “Dear friend,” he wrote to an associate, “I am a man who loves joy and who therefore wishes to see you and everybody happy. If you do as I say, you will be joyful and glad in heart.”