I think you have the right to ignore people. But you shouldn't feel bad for wanting to speak up to them and say what you've got to say
Thats not bad advice. Have you ever said what you want to say?
I just wouldn't know what to say, I'm not good with my words.
I get that sometimes we can all be awkward and forget what to say, but it's not an excuse to just keep ignoring everyone. People will  think you're stuck up or a rude person.
I don't need anyone, I can only rely on myself and I can't hide from life.
You can't rely on yourself for everything. Eventually you'll need someone. Whether it be to give you a job or even something simple like serve you food.