I love the idea of writing to the house, and expressing that nostalgia and the memories that will remain unforgotten. "It laughs an empty laugh" fills me with sadness!
Reading this also reminded me of some abandoned, unkempt properties I've seen recently. Not sure if you're familiar with the hobby of geocaching, I just got into it at the start of October, but it's shown me some really beautiful areas I never would have known existed. My favorite spots to drive to are on country roads, and I visited quite a few small cemeteries yesterday. One was between two houses and had not been taken care of. I felt a lot in the silence. I also passed older barns and houses that definitely have a history, and I can't help but wonder how many generations occupied those spaces.
I read all of this as an analogy too, losing someone that has housed these memories and has been a secure place to build an enriching life. When that person is gone, or parts of the relationship abandoned, the ivy crawls in, the dust, the weeds, the doubts... all of the reminders of what was and what could have been. It holds a lot of weight. Especially if this is tying more to one's childhood, and the pain of growing up and leaving behind what is known, what has become a comfort.