Don't feel bad about the money you spent at the vet, anyone that has any type of pet has a responsibility to that pet to provide medical attention when required, you did the right thing, thank you. I have had several birds with fatty liver and given many meds so I will share with you what I have done, my birds are not hand tame either. Giving the meds directly into the mouth is better because then you know exactly how much is being ingested. I give the meds before sunrise and at night if the meds require twice a day doses. When I do this the room is pretty dark with just a night light on, fill the syringes with the required amount of meds right before you want to administer. Working with just the night light I quietly pull back the cover on the cage open the cage door, slowly reach in and cup my hands around the bird and remove from the cage, give the meds and put the bird back in the cage in the same spot the bird was in when I took it out and cover the cage again. I find that doing this in very low light and before all the birds are awake and chirping helps things go more calmly. I do the same thing at night, after I cover the birds for nightime and turn off the lights, I come back in about 30 minutes and remove the bird and give the meds. Move slowly and quietly and try not to be nervous, after you do it a few times it gets easier I have been able to medicate even the birds of mine that I consider the most hand shy using this method. I never grab the birds after they are awake and lights are on, it only serves to make me and them upset as no bird likes to be grabbed.