That’s just incredible. Well done. Absolutely beautiful.

I read your original post and felt like you both made honest mistakes and weren't trying to hurt anyone. I'm very glad to read that you both have admitted and realized the same thing about your own and each other's mistakes, and are going to try to work it out. Just remember: it's OK if it doesn't work out. I hope it does, and I can easily see how it would since now you both will be working actively at building trust and communication with each other, intentionally, to specifically avoid another such situation (plus, therapy). I just want to point out: "It is possible to commit no mistakes and still lose. That is not weakness, that is life.”― Jean-Luc Picard. The important thing is that you're not giving up now, at the start, when not quitting matters very much, maybe the most, because this is when your investment is lowest, and the losses to cut smallest. Keep working, and if you believe in the future of the relationship, choose the relationship and the future as much as you can without compromising your integrity or safety.

Ehh.... Italy didn't have a border with the USSR (I know, it was really Poland, but still), so that's pretty different.

How many US troops were at Sword, Gold, and Juno beaches at Normandy? How many RAF personnel were lost over Europe during the bombing campaigns? How many RN personnel were lost in the Battle of the Atlantic?
That's just three examples. Yes, the US participated in all of them, but so did the British. To only give them credit where they did something alone is just... willfully ignorant and asinine.

The British most certainly did not "[sit] out the war", and saying as much is a grave disservice to the millions of British and Commonwealth citizens who fought and died against the Nazis, military or civilian.