I think that if you look at the cakes shown in my Flickr "Baked Goods" set (link in signature), they might make you feel a little less inadequate.
By way of analogy:
I am, at age 51, a student musician. I began junior college piano classes in my late 40s, with the first semester followed almost immediately by private organ lessons (yes, I do mean like in real pipes).
As a musician, I will likely remain a ham-handed beginner for the rest of my natural life. But that doesn't keep me from enjoying performances by violinists like Itzhak Perlman, Midori, Hilary Hahn, Leila Josefowicz, and Nadja Salerno-Sonnenberg, or cellists like Yo-Yo Ma, or trumpeters like Alison Balsom, or flutists like Sir James Galway, or organists like Pamela Decker, Peter Sykes, Diane Belcher, Gabriel Dessauer, Chelsea Chen, or Felix Hell, or the recorded legacy left behind by the likes of Maurice Andre, Jean-Pierre Rampal, Jacqueline du Pre, and E. Power Biggs. Indeed, I can sit there and be humbled by kids with wall-to-wall chops (e.g., Karen Electra Christianson on the East Coast, and Suzy Webster on the west coast, whom I first heard when she was barely out of kindergarten!), who can play me under the table without breaking a sweat, and thoroughly enjoy it.
I may feel humbled, but I don't feel inadequate. Indeed, my own musical adventures make me that much more appreciative of the talents of others, because I understand what's involved.
You are worthwhile. Your skills as a decorator may not put you in the same league as some, but they undoubtedly put you far beyond others, and they give you a far greater understanding of what you're looking at than others.