I can totally relate. I struggle daily with balancing depression, anxiety and trying to act ok and be social. So when people around me are talkative and happy, I don't want them to ask questions on why I'm so sad and quiet, I just have to go with. But yes, it is hard to speak, act and get motivated.

I think the word is INTROVERT. Some people are just naturally quiet, shy and like to not interact with people. Depression acts in the same way, you loose interest in almost everything, and you do feel alone. But you are not alone, it is merely just symptoms of depression that every suffers from.

Hang in there things will get better, and you find your voice again.