Wow I didn't know that this was such an issue for so many people that must be so invonvenient for you. Could you take your handbag in with you and a little spray for afterwards? If that makes you a bit less embarrassed.
I suffer from IBS and sometimes go a few times per day. Luckily my work toilets are in a back building with other rooms and storage, so no one knows if I'm going out to storage or going out to do my business. My friends and partner are all aware of my habits and it's actually a bit of a joke that I need to go at the most inconvenient times! At home if ive been on the toilet for a while and then walk into the loungeroom my partner will say something along the lines of "Im guessing I'll give it half an hour before going out there?" And my reply is "Maybe an hour just to be safe" Lol. Having a sense of humor about it made it much easier for me! !