I think it makes it somewhat easier--when it's in their own words it's there for history to judge. If there were just anecdotes from other people, it would be harder. Maybe I can relate--my husband (though better than GV!) feels more comfortable when he gives me cards or writes letters when he's gone. I am more of the mushy-gushy school myself.
Still, I have kept every card, every letter, every note that comes with flowers he's given me--and after 15 years that's a lot! Having some written items may be nice for our descendants to have--I'll have to get rid of the racier stuff though.
So it doesn't bother me that for GV&QM it's mostly in written form and it doesn't seem to have bothered them overmuch, though QM did say early on that she wished they weren't so stiff--I presume that changed over the years and there is a noticeable change in their body language as the years went on.
Much of what we also know about N&A comes from letters and diaries as does V&A and Vicky & Fritz. Sometimes a person can almost feel like a voyeur reading them--especially diary entries.
