There’s nothing different with this being in your 30s than being a teenager. How hard is it to tell a girl you really like her and find her attractive? I told that to guys all the time. She sounds like a nice, well-mannered girl and if she isn’t attracted to you she will likely find some polite way to say so and won’t laugh in your face and say “Not a chance, sucker”.
It sounds like you have some kind of fear of rejection holding you back here, which is something that salesmen and job seekers need to learn to get over because they might have to knock on 10 or 20 doors to get someone who’s interested in what they have to offer. If you can’t even bring yourself to knock on one door then you’re not going to get out of the starting gate. Go for it.