Email - not able to send

Sent email shows up in sent  file but no one receives it.  I am seeing posts here that you are the only one that can help as it may be that you have blocked my email somehow.  I have been on the line with comcast tier 1 and 2 and even security and no one  knows how to help.  They say everything looks fine on their end.  I get emails, but no one gets my sent ones.  Email is   I was on the phone for over 4 hours with comcast.  Please help.