I get you OP.
we had similar as we had IVF to conceive our second child.
DH was on board with not telling his parents during treatment, as they’d have got over involved in the choices around how many goes to give it etc.
once I was pregnant past 12 weeks and we were telling them that he wanted to tell them it took IVF. I did not.
same as you, my private business, I would never seek their support in that situation. I also knew MIL to be indiscreet. She had told DH all about his cousin’s IVF. I’m sure cousin wouldn’t want us to know.
i also haven’t discussed this with my parents for similar reasons.
i eventually persuaded him not to by pointing out if the pregnancy didn’t work out they’d THEN get over involved in whether we tried again etc.
this is a private event, and as you say one that impacted you more than him.
as a partner you have to keep your partners private stuff private.
for me that line is ‘confide in who you want, unless it’s someone and something I specifically ask you not to. AND, a person you choose had better be discreet.’
i do for example talk over private issues in my marriage with my sibling as I value their support and insight.
But I trust them both to never let DH know what they know and to never blab about it to others.
i don’t trust my mum in the same way so I’m much more choosy about what I talk over with her.
what should you do?
i don’t know, that’s harder. Don’t rush.
you feel betrayed and are very upset. Let that really sink in for him first.
its sounds like he’s trying to justify and fob you off.
make it clear how hurt and betrayed you feel.