I have felt like this before. I have entire conversations with my friends and acquaintances in my head but when it comes to the real thing I struggle. I've improved with practice and more self confidence. Before, I even felt like I couldn't contribute to conversations because I either didn't know what my opinions were, or I felt like I had no opinion.

The thing that changed for me was coming out as transgender. Suddenly I was living as the real genuine me and I found I could relate to people better. I also switched my major in university to theatre and met all kinds of people both louder and weirder than me. I really feel at home with these people and find that I DO have opinions, I just needed to become more comfortable with myself to be able to give myself permission to have an opinion.