If there’s one thing I can say having been there as a first responder, don’t ever regard talking through incidents and your feelings about them as weakness on your part. Our local department has a procedure where everyone on a bad call gets assigned a fellow member who will reach out to them and check in over the course of the following days. And offer to hear anything they have to say. If your department doesn’t have such a practice, it might be something you guys consider.
Everyone is different in their ability to rationalize death and deal with the visuals. Even now, my wife who just made Lieutenant after six years, struggles with two really bad calls in particular.
My advice is just to not allow an accumulation of things build up without venting out those filters, and talking to your fire family or someone else if you ever find yourself struggling.