Oh, i feel for you i really do.
Can i share my experience, its not entirely relevant.
Firstly I should say that in principle, i am anti-abortion and feel very strongly about it, but this is my position, if it were me.
I have been with DP for 16 years, he never wanted childre - i had a DD from a previous "relationship". Thats all good. So, three years ago - just as i was finishing uni, i got the BFP (always thought it meant, bloody fucking pregnant!). I was , dp was dumbfounded. There was never any real question that we wouldn't keep the baby as he knew my views on abortion and didn't even suggest it. So, three years on, we are in financial ruins when we should be enjoying a bit of stability and rewards for hard work. We have gone from being the shining example of a perfect relationship that my friends envied, to just about hanging on in there - PND didn't help. I am in counselling and our relationship, im sorry to say, will never be the same again - that makes me very sad. Of course, life is life and i ADORE my DD and DP absolutely lives for her, he is such a wonderful daddy it stops my heart.
If i got a BFP with one child now, i'm not sure i could cope, let alone with twins. I know that if i didn;t have a termination then my relationship with DP would be over - so, the situation is, i would end up a single parent to two children and DD would lose her daddy. I would be devestated and im not sure i could cope with the alternative in my head.
I don't really have any advice, just to say, please don't judge your DH, he is thinking with his practical head, the twins aren't inside him so ultimately it is your decision, but my god, what a decision you have to make All the while you are in the mindset that you would be terminating for your DH then it is a disaster waiting to happen. Whatever decision you have to make, must be joint if you are to come out of this together. I think having counselling is just the thing - I wish you both well, whatever you decide.