Am I engaging in escapism? Yes. Reading and writing about lilacs in the middle of winter makes me happy.
The key to using lilacs in bouquets, of course, is getting them not to wilt. They are notoriously difficult to hydrate, preferring to stay on the shrub rather than on a tabletop. However, it is possible! I've been harvesting lilac boughs for several seasons and I've learned a few methods to condition them to stay fresh for several days. Here goes.
Choose flowers that are 1/2 - 2/3 open and cut the branches as long as you can with sharp, clean clippers. Harvest in the cool of the day.
Remove all foliage and put stems immediately in a bucket with a few inches of water.
Two choices here - either store the bucket in a cooler or cool space for several hours, or go immediately to step 4
Using heavy duty clippers, make a vertical cut in the stem the length of the clipper blade. This aids in allowing the stem to take up water. Do not smash or otherwise damage the stem.
Store in a cooler with clean water for 3-4 hours, or overnight. Note: lilacs do better when held in a bucket with 6 inches or more of water.
Recut branches before arranging. Keep bouquets out of the sun if at all possible.
One more thought - coppicing for better lilac cuttings. I'm willing to give it a try, especially with some of the older bushes.