What type of fasts are you doing? Extended or intermittent (varies) with intermittent I plan ahead of time like say most days I do 20/4 (eating window 4 hours, fast 20) but if i planned going out with friends, I’ll usually just do 5:2, (eat normally maintence for 5 days and fast for 2 days (can varie 4:3 etc)). If it’s intermittent fasting, it’s easy to rearrange it to fit your scedule.
But if you’re doing extended fasting (7+ days), Like you said it’s hard fitting that in with a social life, you’ve pretty much already doing it by saying you already ate or not hungry ect. But you could suggest going out to places that don’t require eating with your friends and family.
I am honest about my fasting and goals. I get a lot of misconceptions and strange input but I am very well informed so I am pretty good and refuting misconceptions.
I have also found that I can attend social gatherings and draw attention away from eating.