amuminwaiting, I'm really moved by your posts, and wanted to say how horrid I think your ILs have been.
It's so hard to share in other people's joy (whether you like them or not, frankly) when you are TTC and have suffered MCs, so I think that you and your DH are wise to try to withdraw from situations that will cause you pain.
The only thing I would counsel you against is allowing your grief for your losses to embitter you against all expectant women or new mothers. I had two MCs in six months, and then spent another miserable year TTC, and the agony of it all nearly sent me demented. I'd run to the loo to cry whenever someone brought their new baby to work, or if I heard that a colleague was pregnant. I felt as if they were having the babies that were rightfully mine.
But four things happened over the course of a couple of months that changed me; I started having acupuncture, which gave me hope and the sense that someone was listening to me; I read an article about Jane Clarke, the nutritionist, who had a hysterectomy in her twenties, and went on to adopt an Indian girl, which made me realise that if I couldn't have children of my own, some good could come out of it if I could adopt women.timesonline.co.uk/tol/life_and_style/women/families/article726867.ece; I got an appointment at an NHS infertility clinic; and I fell out with a close friend who knew my history, and announced her unexpected pregnancy marvelling at how easy it was to get pregnant when she wasn't even trying, and without even once alluding to my MCs and the possibility that I might feel sadness for myself even while I was happy for her. The realisation that I was angry with her for being insensitive and indifferent to my feelings, rather than for being pregnant was a revelation.
I suppose what I am trying to say is that other people are a bloody nightmare at a time like this. So many people mean well and put their foot in it; others just don't get it and are even more insensitive. The only way for you to cope is to try to manage your reactions to other people and their crassness, whether it's well-meaning or otherwise, so that you don't become curdled with grief and resentment and thoughts of what might have been, as I did.
I know this is hard, and what worked for me, won't necessarily work for you. You have to find your own coping mechanism to help you become stronger emotionally, and to give you hope for the future, even if that future doesn't take the form that you expect.
Every baby that is born is a miracle, but women like us need a bigger a miracle than most - and they do happen. I have two boys now and after four years now I still cannot believe my luck.
Be strong, be hopeful, be kind to yourself and avoid people who are toxic and make you unhappy.
I wish you, and everyone else who posted, well.