I often ponder existence. Why do we exist? — Seb

Good, because, 'for the most part', it's good use of mind... [ref. 'for the most part' - I advise you stick to your own theories that aren't accepted socially, and build yourself up from ground zero].

If you enjoy pondering, a lot of people here will tell you, there's lot's of joy and enlightenment to come from such pondering.

It's impossible to imagine there being nothing, so it feels like we and nature HAD to exist. — Seb

Yes... That's one of the questions that drive us all mad.

A common answer is that at the time there was nothing, is actually a conception of 'no-time', for if there were time, there is at least something.

Thinking there is a time where nothing exists is false, that time, is really a mixture of something and nothing, or just something.

'It drives us all mad', a symbol I like to put with this thought, something to think about. Where (I do not believe in God but) even Gods are mad about it.