I didn't work for the first 11 years of my DS's life. It worked for us because my DH also works away a lot, and it provided stability for DS and DD, and I liked to think they were being looked after by me.
However, it wasn't without its problems. I became quite insular and, looking back, probably depressed. Although DH and I were quite happy, I always felt a bit of a drudge, albeit that it was for the right reasons.
When DS started senior school, I got a part-time job (12 hours a week). I did this for about a year, then got a different job which is much more flexible. The first year did involve a bit of juggling, but it has done wonders for me as a person.
The first day in my new job, I was walking through the city thinking "I'm back to normal!" I was no longer just mum and wife, but myself again.
I've lost weight, become interested in so many more things and have new friends. DH has noticed that I've become so much more confident in myself and seems to have far more respect for me (not that he didn't always, just more).
I think when you don't have much except your family in your life, your world becomes very small and you probably become quite boring (I include myself in this).
So I think what he's suggested is a good idea - for both of you. It will give you a new focus and more to talk about. I would keep the home help and get yourself out there to work, I'm sure it will make a lot of difference.
I'm sure that forgiving him and moving on is terribly difficult, but if you've made the decision to do that then you just have to throw yourself into it whole-heartedly.
Good luck.