<human>: My wife has recently developed a habit of going to the spa. We live in Europe; it's a mixed, nude spa. By her own appraisal it's populated 50% by middle-aged men. She's short, cute, and has big tits, so I know she draws attention. I'm sure the female friends she goes with do, too.

This situation bothers me. I spent the first decade+ of our relationship feeling like I was special - unlike others, I got the privilege of seeing her naked - but lately, I'd only have to show up to a spa on the right day. (Well, except I'm not invited, because obviously her friends are there, and they're *naked*, and I'm not a random stranger.)

She's the sort of person who has a hard time relaxing (we're talking anxiety spectrum), but has told me that the spa is one of the few things that actually helps. I can't take that away from her, but if I even give her the slightest inclination that I have an issue with her spa habit, she'll stop it immediately. I know this woman. Moreover, I'd never dream of trying to tell her what she can or can't do with her own body. Instead, I keep silent and feel depressed and un-special about this whole thing until I manage to distract myself with something else.

Fix me, please?

Can you summarize the given text in a few sentences?
<bot>: wife goes to nude mixed spa, I'm a shitty person so that bothers me, but I won't tell her because she needs the relaxation.