I Am Friendly But Shy

It takes me a long time to process what I'm going to say, which makes social situations quite awkward because usually when someone approaches you it requires an immediate response so when someone comes over to talk to me I usually just end up stuttering, not making any sense, or pausing for way too long before rambling on and on about something that has nothing to do with what they mentioned. This is why I find it easier to keep to myself, smiling and being civil when I need to, when in my head I am overthinking everything, coming up with new reasons to avoid certain people. I feel cooler on the internet.