While this is a nice idea, I don't think you should tell your manager that you are feeling guilty for not working hard enough. A good manager might do something positive with that information but you're putting yourself in a good deal of risk saying something like this.

If someone is having mental health, emotional or personal issues they should not look to solve those issues through their workplace and instead keep their personal life as partitioned as possible from their professional life.

GP isn't saying that they are feeling guilty for not working hard enough. Is that they don't know how other people are perceiving their work. So in that case a "how do you think my work is going on?" doesn't hurt at all. If, like others said, you can't talk like this to your manager, there are other problems that need to be tackled.

If you don't feel like you could talk about it to your manager, I think you should find another manager.

Yeah because that's so easy to just grab another job.

I totally agree with the parent poster - keep personal life personal. I never mention anything personal to anyone at work.

I've had 4 different jobs and never felt like I couldn't talk about personal issues to my managers. I'm not saying you should talk about it, it's still a personal preference. But a manager that would punish you for your honesty is not a good manager in my opinion.

In this case, we're not even talking about personal issues, but guilt at work. If your manager can't help you with that, he shouldn't be a manager.