Everyone has an experience of being lonely. The state of feeling becomes worse if you are feeling lonely in public place. Where you are surrounded by the bunch of people you know and you don't have any idea why it feels isolated with that group. I have same kinda experience and I was finding the cure for the feeling lonely. There are different reasons that are the responsible for feeling lonely and different ways to fight against loneliness.
People, sometimes they will not try to connect with you not because they don't want you to be there. But people are reserved with their thinking and unaware of their actions. It is your responsibility to start the conversation and make the connection with them. On other the hand, you have let them know about your presence.
The state of feeling lonely gives a great opportunity to utilize the being lonely into thinking as by being yourself. This is the period of our life to endure us. Time being lonely will not stay longer and there are so many people having the same feeling. It is way worse than you have. It is a short period of life to test yourself and making better of yourself. We have to be grateful for this life that God has given to us.
Also, it is a great time to talk with God and listing to his word by your heart. According to his response, making changes in your life. It helps in purifying thinking and enjoying the experience of peace and joy inside your heart.
