You must be investing most of your time in the activities where you don’t accommodate other people. This kind of approach in daily life will make you feel alone and it acts as a barrier between having strong bonding with friends.
You should try to spend more time with people to know them better. Try to plan out activities together. You should not inhibit yourself from taking initiatives and sharing your problems with others. Join activities where you can get an opportunity to interact with other people eg. sports or dance etc. Slowly you will be sharing better relationship with your others.