I guess I was very lucky with this one. The people who knew and know about my surgery (or rather multiple ones) are/were usually curious but not hostile. When going to restaurants or ordering food for special events they usually ask what I can eat or not (I don't eat meat/dairy) and if I'm ok with the choice they made.
I can remember being at a fancy dinner after a meeting and one of my colleagues noticed me not eating that much even though the food was sooooo good (it was) and I freely admitted that I'd sometimes would like to be able to eat more, like e. g. tonight but that things are just as they are and that in the end it's not the end of the world. He asked some questions, I answered them and then we moved on to a different topic. I gave a damn that we we're surrounded by people. I'm not making it a secret, too much of a hassle.
Of course I can't look into their heads and I don't know if they're talking negatively about it behind my back.
I'm sorry to say so, but WLS patients are contributing to this stigma themselves by keeping their surgery a secret, sometimes trying to hide it at all cost and telling people they "just eating healthier and exercising" when asked about how they lost so much weight.
This "keeping it a secret" is usually explained with wanting to keep medical privacy. While I completely understand that medical history is private I still would like people to ask themselves the question if they would be as private about going to the dentist because of wisdom teeth surgery or having taken their gall bladder out. In fact "gall bladder surgery" is a popular camouflage for WLS as it seems, so "medical privacy" doesn't really seem to be the issue in the end.
There will always be toxic people in your environment. You can only try to get rid of as many of them as possible or at least limit contact to them as much as possible.
Regarding first dates with guys: maybe try to meet them for coffee first, not for dinner. No eating involved at all or maybe only something small.