Thank you for the query.
Unfortunately there is not much that can be done with improving sitting comfort at your case. You have had an abscess
which were incised and the wound were left open. This is how it suppose to be done. And this open wound needs time (and only time can help here) to clean itself and get healed. It can takes even 2 weeks. You may try to take some painkillers, however not much can be done to accelerate the whole process. I assume that you do clean this area every day.
So you should rather be patient, avoid sitting in the way it hurts and maybe take some time off the work.
Hope this will help.