Repairing the friendship with Don

Hi, I googled everywhere how to fix the friendship with Don. I left her inactive for a quite long time and she was full of red bar with Don. She doesn't have any pink bar with him. Her traits are Genius, Outgoing and Neat. She doesn't have any bad traits but I have no clue how she got bad friendship with Don. I don't know what happened with him while she was inactive. I tried to let her use lots of friendly interactions but Don keeps being mean to her. I'm not trying to go for romance with him. She is already engaged with my vampire sim. I just want to get the green bar with Don. I feel uncomfortable whenever she goes into gym as Don always shows up at gym. I want to know how to fix this without mod or cheats.

https://1.bp.blogspot.com/-wuo623yByRw/W1XFpp4ZUTI/AAAAAAAAA8A/y14kKGXROI02ldRPnE1wzGzKzIhXZ86sgCLcBGAs/s1600/Screen%2BShot%2B2018-07-23%2Bat%2B13.07.59.png