I agree acrossthepond
I know, absolutely, what a wonderful source of advice MN is and that it is coming from a good place but just lean off MrsHW a bit please.
It is absolutely headwrecking to be in this situation and it is also headwrecking to have people tell you things with absolute certainty that you cannot believe even if deep down you might know there is some truth.
MrsHW is playing this absolutely right.
Priority 1: do not get pregnant and do this without him finding out. If he thinks you are pg let him. It is safer.
This might be frustrating for posters who want to shake the OP awake but by not doing what he wants over this is already a massive step towards independence.
Priority 2: think about how life is now and what you want from it (MA) and what will make that possible.
Priority 3: look at his behaviour and you response to it and really observe if this is what you want. You are already starting to do this.
Picture your mini carrot rebellion. 
It is your life MrsHW. You must choose what you do. Otherwise you are swapping one person telling you what to do for another set of (very well meaning) people telling you what to do.
You are doing brilliantly OP. You are looking afresh and managing to voice the things that happen in your rs that you are uncertain about.
You don't have to tell anyone in rl if you don't want to but if /when you do rest assured WA are brilliant and you have nothing to be ashamed of.
I know other posters really want to set MrsHW free from this rs but a decision that is come to in the OPs own time is one that she is far more likely to be able to stick to and carry out.
It is much better to wake up slowly and to go when you are ready than to stay sleeping.
Take care of yourself MrsHW. I really feel for you as this must be a tough process to go through. It has been a hard few days. Just the realisation that he would try to force a pregnancy on you is a big realisation.
Be kind to yourself
big hugs. We are all wishing and hoping for you.
And please be gentle with the OP.

Those of us who have left might look back with hindsight and hortor and think those hesitations were wasted days and wasted weeks and we should not have spent one more minute of our lives on those Fuckwits. But they were not wasted. We were taking our time growing our wings and our armour and getting our running shoes on. Its better to do it later and well prepared and successfully than not at all.