Why is my skin so awful when I try so hard to keep it looking nice?

I have tried every beauty product under the sun and am leaning towards the most expensive lately just because they seem to be the only ones that do what they say on the tin. My skin is very spotty, greasy, dry and I have noticeable veins all over my skin. I also blush easily and have very visible pores and basically my skin is just the worst! I have tried god knows how many products which promise to help but none make any difference whatsoever! any thoughs?