I think I’m extremely weird for this, and I try to explain it as good as possible.

See, whenever I do something I enjoy, be it designing something in CAD for fun, working out at home, watching a new show I enjoy, playing video games… it goes well as long as I’m completely alone. But as soon as someone even as little as encourages me, I loose all interest in this and stop doing it for some time until I am alone some weeks, months or even years later and I do it again, have fun for some days, and then someone finds out what I’m doing and I just stop it.

Is this normal? What is this called? Is there help?