I'm sorry to hear you're so discouraged.
I don't know if it helps, but there is a low-tech method called the Walstad method that, for me, has been very reliable - without CO2 and without fertilizers. You can even run them without filters, but I don't.
If you're interested, read Diana Walstad's book "The Ecology of the Planted Aquarium". I can't promise that it will be a fun read, but there is a TON of research and science looking at what is happening in the aquarium, and she puts forward a common-sense approach for keeping tanks.
And if not, sorry to see you go. Maybe in a few years the bug will bring you back!