Ouch, that brings back memories - my episiotomy site was not infected but completely broke down and I had to be operated on a week later to repair.
Only advice I can offer, Anne, is after bathing, put the hairdryer on a cool setting and blow dry affected area. I was told this in hospital, its important to keep area clean but just as important to keep it completely dry, as towel drying does not always work.
We bought D-i-L a foam rubber cushion with a hole in it in the appropriate place! made all the difference. Seem to remember we got it from one of those medical supplies/ disability places.
had episiotomy last october - unfortunately mine got infected so tell whoever has had one to be very careful when washing/drying etc. I used witch hazel on a pad - cool relief - the mid wife recommended it - i got scared because when i read the bottle it said not to apply to open sores/cuts, but midwife said would be fine and she was right. Wish somebody had told me the tip about the hairdryer. Unfortunately, only time can heal. we're lucky in that our sofa is quite wide as i could get on and off without actually putting pressure on the problem areas and could lie on my side (fractured coccyx too). hope she feels better soon - not a pleasant experience (i sometimes think the stitching was more traumatic than the labour!)