Do not let doomsdayers get you down! You are already well past your surgery. Your stomach tissues should be all healed and happy. You just have to follow your program, know it’s a journey not a race (don’t be bothered by plateaus).
This kind of talk by your co-workers is common — ever notice how when someone in a group is pregnant or has a major illness people will start sharing stories about how they know someone who had something similar but there was a freak occurrence or bad outcome, etc.? “My sister was pregnant with twins and she was in labor for 36 hours!” “My Aunt Ada had kidney cancer and her left leg just popped right off one day! They never did find it.” They are just connecting to the experience with storytelling, which is pretty thoughtless (but a good reminder to be mindful ourselves that we probably do it to other people and should watch out for that).
Next time you hear talk like that, smile to yourself and know you are completely in control of your journey, you are rocking it in every way and you are a success. If you feel the need to say something, maybe a breezy, “Oh, I think the docs I’ve had care with have everything under control just fine.”