Your symptoms are highly suggestive of blepharitis to me. Crusts, stickiness, redness, watering are all suggestive of that. You may require a course of oral doxycycline. Along with this warm compresses need to be done frequently. A preservative free lubricating drop like Refresh tears should also be used. It is often difficult to treat severe cases of blepharitis but it is certainly treatable and doxycyline course is very likely to help. You can discuss it with your ophthalmologist or see another one. Thanks and best wishes.
Please, click the ACCEPT BUTTON so that I can get my dues. BONUS and a POSITIVE FEEDBACK will be appreciated.
I would advise you to get a repeat lab diagnosis to confirm whether it is still the same infection or now other organism is causing it. Tear duct infection can be caused by Serratia and it may cause dacryocystitis. However, it would be prudent to repeat the lab diagnosis. You can discuss it with your ophthalmologist. Thanks and best wishes.