My goodness some people are mean. It seems that people feel they can use the anonymity to be nasty. Just ignore the horrible messages and don't take it personally. Not everyone is like that and you can choose which mums you spend time with in real life. It's like anything (kids or no kids) you gravitate to people you like and same with motherhood.
I was happy childless and didn't want to be a mum. Got pregnant by accident with my husband) and love my child more than anything. Best thing to ever happen to me and so glad it did. In fact we now want more. It is hard (lack of sleep, the crying etc) but it is soo worth it seeing them grow, develop, laugh. It's honestly magical (and I hated kids!!) Although my husband is the best and I am quite selfish so he does A LOT (nappies, nights, food for everyone, cleaning, makes sure I have time to exercise, get ready properly etc etc) and I don't know how I would do it alone but that's just me!!!
41 isn't too old to have a child, but also it might be your last chance and you need to decide if you terminate if you're OK with that and can live without regret.
If you really don't want kids and you know that, then terminate. But it sounds like you're questioning it. It is a big sacrifice. I didn't want them as I knew all the negatives... no relaxing lay ins, be tired all the time, not be able to go out when I want, not be able to do far flung adventurous holidays, have to give birth, the changes to your body etc etc but what I didn't account for was the unconditional love and adoration I would feel that makes everything worthwhile. I have embraced the fact it's just a different life experience and joyful in different ways to being childless / carefree.
Good luck whatever you decide!