Oh hun, I've been down that road many times, and I've been getting better when it comes to this situation. What I do is try to be another person, see what it feels like to be "in" the group rather than the "outcast". Maybe talk to one of your friends about your problem and then they'll try to bring you in the conversations. If they are loyal to you, I'm sure that person will have no problems helping you out! That's what good buddies are for, after all.
Some time later, you'll get used to being apart of the conversation and you'll talk to your friends more and then, later on, you'll feel ready to talk to more people. It's just a gradual process that will get you to your goal to talk to people! You will get there for sure. All you have to do is start small!

I really hoped this helped! Keep posting ITM.