Your not doing this for your co-workers, so ignore them. I have people like that around me like that too. "are you sure this is safe?" my response a hell of alot safer than carring around an extra 60 lbs. Don't give up or feel negative, thats what they want, people like failure its easier to talk about. Try a support group, you'll meet new friends. I thought I would never do that , and now I look forward to going to more! Good luck