Embryos do not get implanted by iVF. They are transferred, and then if you’re lucky, the embryo implants. She didn’t decide to have twins. She probably had two embryos transferred in the hope that one would implant, and two implanted. So here we are.
OP you sound like a good friend. She’ll need support, maybe a meal train for the Mum, help around the house with laundry and cleaning, some adult company, if she can afford it maybe a night nanny, and possibly help with feeding the babies depending on how she’s tackling it.
Lots of people have suggested helping her get as ready as possible before the babies arrive, too. That would be helpful.
I had a baby in my mid 40s. The whole experience has been the biggest blessing in my life. My child is happy, well balanced, and has all of mine and her Dads love and attention. Maybe we’ve had a gma comment here and there, doesn’t bother either of us. We laugh all day every day.
I’m friends with other parents who have kids the same age as mine, and some of these parents are young enough to be my child. Nobody cares, we’re all busy raising our children, sharing our experiences, enjoying our families. No gossiping at the school gates. Your friend OP will be fine, better than fine.