My scalp (and skin in general) is really oily. I can't go a day without either co-washing or low pooing, and I've been CG for a year now. I can only co-wash 1 day in a row. If I do it two days in row, my roots get OC'ed and flat. You didn't mention if you were exclusively co-washing when it was a disaster or not, if you were you may try alternating.
You can "protect" your hair from the low poo by putting conditioner on the length of your hair before you low poo and concentrating the low poo only on your roots.
I think most of us have been incredibly frustrated with our hair. While you're figuring it out, you can try some fun hairstyles. Updos, braids, etc.
One very last option that I'm not necessarily recommending: Was your hair "better" before going CG? If you've been doing it for a year, and it's not working, you may want to try to go back to sulfates/silicones.