Hey Cindy... Certainly no need to apologize and condolences on the passing of your neighbor.
As for you wanting to learn to Mask your Gaussian Blur filter, it's easy-peasy... Once you know how.
For me, Masking was One of Those Things that needed to "click", I needed that "ah HA!" moment and once that happened it was all downhill. I don't know if you want to have a conversation about how to do this or not, but I'll put out some information that might help. I think you're pretty savvy with PS in general so I'm going to make some basic assumptions about your knowledge of getting about in PS and how it works.
To Mask a G. Blur filter you're going to first duplicate your Background Layer and rename it something like "Blur Layer" (for example). On the Blur Layer you're going to apply your Gaussain Blur from the Filter menu with whatever parameters you want. This of course blurs the entire image but that's what you want. Once you've gotten your Blur on you're going to apply a Layer Mask to the Blur Layer by clicking on the "Add Layer Mask" icon at the bottom of the Layers Panel. The Mask, by default, will be white. At this point you're going to need to make a decision about HOW you're going to mask the G. Blur filter in this particular image because Masks are either White or Black. You've heard the saying, "White reveals and black conceals", right? Well that applies to Masking. A white mask will show your G. Blur filter effect while a black mask will conceal the G. Blur Filter you applied. It applies to the Pen tool as well and the Pen Tool you choose will always be the opposite color of the Layer Mask; so if you're going to use a White Layer Mask you're going to use a Black Pen Tool and vice versa; Black Layer Masks require a White Pen tool.
So, to reiterate, you're going to have to choose between one of two options:
1. Apply a White Layer Mask and use a Black Pen. In this case the White Layer Mask is showing the G. Blur effect (white reveals) and the Black Pen covers it up (black conceals).
2. Apply a Black Layer Mask and use a White Pen. In this case the Black Layer Mask is covering up the G. Blur effect (black conceals) and the White Pen uncovers it (white reveals).
Examples:
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Hope that helps and my apologies if it's more than you wanted to know!