Sorry havent read through all the comments yet but to all the folk say ditch her - the trust is gone, let's slow down a bit!!
Did she do this deliberately and do you know that for sure? Cos the answer gives two very different scenarios. It is one thing to not plan for a baby, it is very different when you are in a situation where you have done everything right and still end up pregnant..... which does happen, trust me!
To say we have 5 kids between us, let's agree to not have any more is totally logical and reasonable and rational cos there is no real baby involved.
To say we agreed not to have anymore, but now that you are pregnant (if she did everything right) you have to stick to that and get rid of it is very different is a very different conversation. This is a baby that exists, that is a reality.
You say she keeps flying off the handle when you mention it..... so she f*cking well should. She trusted you to be the person she could turn to and instead you are sounding like a two year old having a 'you promised tantrum' unable to see the goal posts have changed.
Yes you had that conversation, yes it made sense, but that doesnt mean it doesnt warrant another calm and sensible conversation now rather than just saying 'you agreed'
You said you would always be there for a child.... how do you feel now one actually exists? Like take a minute and think about that and where you stand... maybe nothing has changed and that is totally fair enough.... but you have to recognise this conversation is very different to the one you had before..... it's not hypothetical.
Just to point out from her point of view.... you are acting like an asshole. She is terrified, not only is she pregnant with baby number three but she may also lose you as a result!
Just to clarify I am basing all of this on giving her the benefit of doubt that she is innocent in this as like I said, I know from experience it can happen.... I did everything right and still got pregnant.
That said if she did it deliberately then forget everything I said above and tell her to do one!