Hi there,
Yes this problems can be very frustrating. I have struggled with trying to understand why some people have trouble and other people do not.
There are some classic risk factors for wound healing problems that include:
diabetes, obesity, smoking, collagen vascular disease, poor nutrition, immunocompromised state.
but sometime, we just do not know. It sounds like you are doing all the right things. Now this is the hardest thing to do but you have to figure out how to allow time to pass and let your body heal at the pace that your body has.
bets wishes