I had (and still have) a similar issue from time to time. In my case, it is rooted in unstable self-esteem and unhealthy perfectionism. Like, I tend to think that if I'm not the best, than I'm the worst. So if my implementations of any ideas are not perfect, than they are disgusting and I should destroy them. I was especially inclined to such an unhealthy way of thinking, when I was younger and more emotional, than now.
Luckily, I think that I slowly overcome this issue by critical thinking and support of others.
Particularly, I'm trying to look at my creations as detachely, as I can, to distinct them from myself and don't let my psychological problems lead me to cognitive bias and inadequate estimations. For example, I often imagine that my creative work is not mine, but my friend's, and I estimate it from this perspective. Usually it lead to much more adequate and friendly estimation, then when I concentrate on fact that it is my own work.
Also I often remind myself that there are people who like my creative works, so it means that they really have found something interesting in them. It helps, that I know some of these people. Particularly, I know, that there are some very smart people who enjoy my work. And there are some people, much more experienced in art, who still enjoy my work. And there are very different people with different backgrounds, age, gender etc who still enjoy my work. Not much, but there are still real people, from what I know. It is unlikely, that all of these different people (many of which I respect), would like just some shitty trash. If they found something in it, I can do it, too, and stop seeing only bad in it.
I hope you will extract something useful for you from my experience!