Grief seems to hit everyone differently. I think our partners are doubly hit when we get pregnant again by feeling helpless- especially in the face of not only a rocky pregnancy for baby, but also for our health.
Maybe asking him to set mini goals of his readiness? Like at 12 weeks he'll attend an appointment or something. It is scary, but I also think meeting face to face with the care team (for him) can help ease fears. You can even give your team a heads up that he's coming to the appointment so they can know to give him plenty of time to air questions and concerns.
Sending healthy thoughts your guys way!
2008-Our Baby Girl, PTL born too early at 30w6d, Fought so hard... Forever Loved & Missed
2010- Lil' Bro, Pre-E at 29 weeks... Induced at 36w6d, Born 37w
2012- Lil' Sis, Super-imposed pre-e at 25 weeks, PTL & GD at 35 weeks, Evicted 36w