For the comment about oiling...
as one of the others has said, I don't think you can OVER OIL our longarms. I usually start my machine in manual mode (off to the side of any quilt that's loaded), and start oiling. I can tell by the "sound" when she's no longer "thirsty".
For the comments about losing interest...
well, that happens to all of us.
For me, sometimes I just don't feel like doing ANYTHING quilt-related... or even sewing related. So, I stay away from the sewing room for a little while... maybe spend my time reading, or messing with my farm stuff, or whatever. Then, I will see something that will re-ignite the fire, and off I go again, sewing and stitching away. Sometimes it's the weather, sometimes it's just LIFE overwhelming us all. Don't beat yourself up about it, just give it time. You may find the fire re-ignited, or you may find that your time is better spent on something else - gardening, times with grandkids, whatever. If it's the latter, then you need to take stock of your sewing/quilting tools and equipment, and decide what to keep... or not.