I don't know what to do with my skin! What the heck is wrong with it and how do I fix it?

I don't even know if my skin is dry or dehydrated at this point - or both? It feels very tight/dry after I wash my face or take a shower. It's not flaky or white. I have a mild rosacea so the extreme dryness or dehydration really irritates it. I use a serum which helps but it's not enough, and when I put moisturizer on my face, especially where the rosacea is, gets really shiny. I don't understand why it's shiny though when there's no oil or sebum,, how can there be when I JUST put moisutizer on? It's really frustrating. I just want my skin to be hydrated and soft and normal. Can someone help me?