Welcome Jay, you are certainly not the only one and I am so sorry for your loss. It’s 5 years since I lost my lovely wife to the big C and I have never got rid of a single piece of her clothing, or anything else of hers. You are not alone in wearing her clothes either. I wear my wifes clothes often, sometimes daily, some fit me well even though I was head & shoulders above her. A number of her tops fit me and I wear them often, her panties fit me and in these cold winter months I wear them daily. Her bras actually fit me although the cup size is a little bigger than I like but the hug is the best! I, like you, have plenty of my own femme clothes but the comfort derived from wearing wifeys stuff is beyond price.
You will get lots of love & support here.