I have a Seroma 4+ months after surgery, will it absorb?

[Smidgesplace]

In January I had my hardware at L5 S1 removed. It was causing severe crippling pain for reasons too extensive to go into here. Along with removing my hardware my surgeon also removed a bone he called the "Larimer" bone. My recovery has  been worse than when the hardware with T-lif was done in Sept 2015. What was supposed to be a 6 week recovery is now over 4 months. At Easter I started trying to return to my normal activity level. Since then I have been in just as much pain as before surgery. I still have healing pain along with disabling sciatica all the way to the bottom of my foot. Worst of all a stabbing pain over my donor site that leaves me unable to move. My poor husband is getting his muscles worked out having to carry me when it happens... Luckily for him I'm little.
Finally after a CT and an MRI my Dr. said he found a small Seroma at the surgery site. It is right against several nerves. He says that because I'm so small I'm super sensative to it.
So here's my concern....today I was sent to have a cortisone shot at the area of those nerves. I guess he's not draining it because he hopes my body will absorb it on its own.
Is that possible this far out from surgery? Or is this thing calcified by now? Are we just delaying the inevitable of surgically removing it? Can a calcified Seroma be absorbed? Or will this pain return shortly and surgery be in my future?
On a side note. I'm not complaining. I'm thrilled that structurally it looks like my surgeries have been successful! All of this pain is just from this little ol' seroma....and that's fixable without resorting to major surgery all over again...hallelujah!
Which, considering I had a pars defect with the worst case of spondylolisthesis possible (my disc was slipped at a 4+ and literally just hanging off the spine into the body cavity) that news is a miracle! I and my surgeon were bracing for the worst case scenerio coming back as the result to my most recent testing. Hard to believe that SO much pain can be the result of something so insignificant!