be hard on (one)
1. To treat one overly strictly or harshly. Please don't be hard on Tessa—she's such a sensitive kid.
2. To be unfair or difficult for one to endure. It's hard on me to watch you suffer like this.
be ˈhard on somebody
1 treat, criticize or punish somebody too severely: Don’t be too hard on little Emma. She didn’t intend to break the cup.
2 be unfair to somebody; be unfortunate for somebody: It’s hard on the people who have to work on New Year’s Day.