I would make your plan for tonite to have NOTHING to do with the content of the conversation, and CERTAINLY not on any outcomes or decisions coming from it.
My counsel to you would be to make a goal for yourself that is centered ENTIRELY on how you react to what is said -- how you come across.
"I will be calm, I will thank him for his honesty, I will validate and I will listen." THAT would be my mantra.
If you could pull that off??? No . . . change that . . . WHEN you pull that off . . . you will have taken a HUGE step.
The decisions aren't going anywhere anyway, right?
You need to be able to learn this skill anyway (how to react to disturbing news without attacking or flipping out); the fact that it will likely ALSO make you more attractive to your husband . . . and make him feel safer about re-committing 100% to the marriage . . . is a bonus.