The way I see it, there is no reason for existence for any of us. There's no plan from the get go, but that isn't necessarily a bad thing. The fact we exist at all, in my mind, is a miracle of random chance, statistics and scientific accidents, or perhaps some form of other power. Either way, it is something that has happened, and really, that means we should embrace it.
A random opportunity shouldn't be missed, so even if we have no reason to exist, we can find a reason to live and enjoy ourselves in our own way.
Knowing or feeling this gives me a sense of purpose and realism, and allows me to think about things in a way that weighs up the fact we have this time to spend and only one chance to spend it how we like. Some people don't like this view, and I 100% respect that. Tis simply how I am.