I'm just a novice, but I'll tell you what HAS worked for me. I have all of my plants indoors now, (I live in zone 7b). I have mostly Phalaenopsis. They are all in a South facing window. When I get a plant, the first thing I do is repot, commercial growers have perfect conditions for growth, but the stores that sell the orchids usually don't know how to care for them, and they have them potted to sell, not to thrive! Often the mix will be dry as a bone, or soaked. I do not move them around, they get watered once a week (unless they get really dry), I only repot them when the roots start to outgrow the pot, or AFTER they bloom. As for fertilizer, I use a very weak solution every other watering. So far they seem to stay rather satisfied with this formula. I've had most of them for 6 months to a year, and they have almost all bloomed. I'm interested to see how they do this summer then they move out to the covered patio.
You mentioned that the real trouble started after you moved, that was probably the killer. I've had buds fall off after bringing a plant home from the store. They don't travel well.
The roots and light seem to be the determining factors as to the overall health of the plants for me. When I repot and find any roots that are thin and soft or dry, I just cut 'em off. I figure that its more healty to have a small bunch of healthy roots than a large bundle of rotting and over-moist (fungus breeding) roots. Indirect and bright light is a must. Make sure that your pot is draining well, these plants don't need to be wet, their roots can absorb moisture from the air and the medium that they are grown in.