First of all, you may want to pick up Vim; it has a vastly superior feature set along with everything vi has.
That said, it takes discipline to learn. If you have a job and can’t afford the productivity hit (without getting fired), I’d suggest taking on a weekend project for the sole purpose of learning the editor. Keep its documentation open as you work, and be disciplined enough not to chicken out. As you learn more, become efficient and start relying on muscle memory, it won’t be as hard to stick with it.
I’ve been using Vim for so long that I don’t even think about what keys to press to search or navigate or save. And my hands never leave the keyboard. To use Vim is one of the best choices I’ve made in my programming career.