@whyyy321 I hear everything you say and I'm sorry to hear that you lost your mum.
I think things are a lot different now to how they used to be. We as mothers work more for a start and also enjoy the independence we've been so used to before children - the load is a lot bigger/heavier!
Everyone's circumstances are different as well (money, childcare, work etc) so we need to make sure we don't compare our load/stress/anxiety with anyone else's and decide we are being feeble or not trying hard enough if the idea of an additional child seems overwhelming. Easier said than done, I know!
I'm in the exact head space you are re: sibling as I too have a great relationship with my sibling and feel dreadfully guilty for DS that I might deprive him of that - but there is no guarantee that siblings will get on!
I've done a lot of reading online from "only" children and a lot of them are very happy/wouldn't change it, in fact most of them are but I also appreciate these articles can be biased.
I also think that we should trust our gut more. My desire to have children was all consuming before DS (20mo) was born, I simply don't have that for a second child even though I always dreamed of having two. I am so happy with just DS, he completes me (maybe that's selfish and short sighted?) but I feel like I am and will be a much better mother to him without chronic anxiety and giving him the love and opportunities that I am currently able to?
Also, when I feel very overwhelmed and stressed I imagine that moment but with another child, HELL! haha.
Single child families are becoming more and more common and I think the societal pressures of having more than one are so huge, so much negative langue and assumptions around having only children, the word "only" for a start. A lot of the myths etc are debunked now too.
I have genuinely thought about this every day since DS turned one, its so annoying but im going to continue trying to take each day as it comes, keep reading, keep talking with DH about what 2 kids might look like in various circumstances (house, money, childcare, car, holidays, extra curricular, time together, stress, work, anxiety etc etc) and keep chatting about the why's too and just trust that the answer will come. GOOD LUCK to you too and try not to worry :( x