Talk about a twisting of Scripture.
Luke 15:1-7- Now the tax collectors and sinners were all gathering around to hear Jesus. 2 But the Pharisees and the teachers of the law muttered, “This man welcomes sinners and eats with them.”
Here it shows that Jesus ate with sinners, exactly the opposite point you mum is making. Although it goes on to say they rejoice when a sinner returns does not change the fact that the Scripture shows eatting with sinners is ok.
In 1 Cor in says not to eat with a brother or sister that is engaging in some specific practices. I am not sure if you are engaging in whatever you were disfellowshipped for, but if you no longer claim to be a practicing JW then the Scripture does not apply.
There is a detailed article on why disfellowshipping is wrong at http://www.jwfacts.com/watchtower/disfellowship-shunning.php