Baba, I was in your situation in the past. Got too friendly another man (work colleague), got found out, was forgiven by husband, had another baby (our 3rd) and then he decides he could not forgive me afte all, when youngest was 11 weeks old. I remember writing on here over 4 years ago asking if I should stay or go (we were still married, giving it a go but I knew we were not really happy). In the end, it was not my decision to make, my H made it for me by telling me it was over. I was destraught, single mother with 3 young children, H didn't move out for 9 months (slept in loft room), very very difficult time. The worst time of my life ever actually. Although we were not happy and I was thinking of leaving (don't know where I would have gone to, mind you), I think if we could have stayed together I would have. Now 4 years down the line (nearly), we are VERY good friends, he has a girlfriend (who he left me for eventually) and I have a new man. I still live in the family home, not seen a solicitor so still "legally" married, not even separated. It is bloody hard, upsetting, awful but if I am being realistic I know we could not have been happy together and we both are happy now.
I can remember being 8 months pregnant and walking out of the house at 2 am in the morning, getting in my car, driving to Brighton (about 1 hours drive away), crying, thinking "if I killed myself tonight, who would even be bothered". I used to "run away" and then when I realised that my H was not coming after me, I would have to swallow my pride and then drive home!
It is hard, my life is different but not necessarily worse. Just different.