I’m assuming here that your partner genuinely wants the relationship to work and is a mature enough person. Well, here’s a “mirroring” technique that can be helpful and works wonders for me.
Have your partner repeat to you what is being heard because often your partner may be hearing something you’re not saying.
For ex. if you say: “I think that if you went to bed before midnight, Sweetie, you could get up in time to get to work on time.
He might be hearing: “You’re not acting like a grown man. You obviously don’t know when to go to bed, so I’m just going to be the adult here and tell you what to do.”
Since you were giving him constructive criticism, this was not your message at all, but maybe he’s had other people boss him around and tell him what to do all of his life and at that moment all of those other people are there in the room and he feels you’re their spokesperson, and he’s sick of it all, so he gets mad at you. Now you don’t know he heard what he did, but if he mirrors what you say by repeating it, you’ll know it and that will give you a chance to respond to what he heard and clear things up.
Hope this helps.