Does anyone know something similar to this manga?
I liked it very much and I would like to read more of a manga about marriage which is smooth and comfortable. Not too much useless angst and drama I hate that.

If you want a steady cozy couple with a reasonable relationship, I'd recommend Bonnouji https://www.mangaupdates.com/series.html?id=31270 There isn't a military or historical background though, but the atmosphere is peaceful and the cute, hearty moments are the main points of this.

I have read this before
Thank you

If you are fine with novels, then Hokuou Kizoku to Moukinzuma no Yukiguni Karigurashi (Novel) and Risou no Himo Seikatsu (Novel) both fit your request.
Especially the first one, it's exactly like what you are describing.

I am reading the first one currently

I just finished reading the first novel recommendation, Next I'll read the second one. Thank you 😀

worrying is just wasting time