Loosing my ability to relax and enjoy things

I am finding myself in a very familiar position. I have a week off. Well, only two days to go really. I had work I wanted to do, and I was looking forward to spend some more time with my partner. So, there was no big holiday plan, just chill out, rest and enjoy the time together without thinking, or stressing, about work.
But as it happens very often I end up feeling bad about how I use my time.
It seems that it doesn't matter what I do I always feel like I have wasted my time. I have never done enough. The things that I want to do become obligations I impose on myself. So much that I can't barely enjoy doing them. It becomes something I have to do so as to not feel bad.

The same happens when I am working, almost everyday I end up feeling bad that I have not done enough work considering the time I have invested, to which I add feeling bad that I work too much and have little time for my partner and/or myself.
The fact that I mostly enjoy working doesn't seem to make things any better. What happens is that all these feelings end up stopping from being relaxed and enjoying the work.

I have been thinking about this for quite some time and I really don't know what to do.
I don't seem to be able to stop it, or change it. It is really taking away joy in everything.
I am not sure where it comes from.
I am really stuck with it.

Today I have people coming over for dinner.
I have started working on dinner early, trying to avoid being stress about it, in the hope that I can then enjoy the evening more. I kind of like cooking.
I already feel that it is taking too long and that I have other things I want to do today, and at this pace I won't be doing them.
To that I have to add that I still have work to do and I didn't want to have any work to do over the weekend, as I thought the minimum on being off for a week should be having my weekend for myself.

When I invited my friends I was worried that this might happen. It is suppose to be fun, I like being the host. But apparently I just can't relax and enjoy things anymore.

Would love it if someone had any suggestions, or just to know that this happens to other people as well, and hear how the handle it.