Hey Ohdeargod, firstly, a surprise baby isn't called that for nothing... and as we al know some surprises take some time to get used to!
I too have pcos and when I fell pg with my ds (a 'surprise' also ) I was pretty down - DD was 2.5yrs, mind, but we were only just getting on an even keel with our finances and stuff and, well, our relationship wasn't in the best shape (he basically ignored me the whole pregnancy). THen my Nan died (I was V close to her) and regular bleeding (hello, guilt, for kinda wishing the I'd never fallen pregnant) involving hospital stays meant it al seemed like it couldn't have come at a worse time...
But I'd shake myself up with thoughts such as 'So many women (especially those with PCOS) struggle to fall pg - I have to view an oopsie as a blessing...'
And 'Everything happens for a reason, it may not seem obvious now but I will look back and know one day'
And other such 'platitudes'...
It's human nature, a mothers instinct even more, to just...cope. You will cope. But if you really come to the conclusion that you don't think you could then remember there are support groups/counselling that will help you with that decision.
Lots of love to you.