I had a year like that last year. No idea why I wasn't seeing them. It gets old, especially when you know they are around. I saw 15 deer over the entire season last year on my land, and 8 of them in one group. This year I've seen 5 times that many already. Sounds like you are doing alot right, don't give up. Maybe try some different tactics to see if that works. Hang in there.