Bad breath detectable by only some people

does anybody know if it's possible for your bad breath to be smelled by some people and not by others?
i'm almost 100% sure i have terrible breath, based on people's reactions when talking close to them (cover their nose, back off, etc), having a bad taste in my mouth and flat out being told by my sister. whenever i talk to people at work, they always cover their nose, and ONLY when i talk to them, never when anybody talks to them.
anyway, i asked my mom and my doctor and they said it doesn't smell at all!
i'm completely confused. has anybody else experienced this?
i'm trying all the cures i can (k-force, visited a breath clinic, take great care of my mouth and tongue) but this is still happening. VERY FRUSTRATING AND DAMAGING!!! Tweet