I am so sorry that this happened to you, it is really a tragedy that women are given episiotomys at all, they are almost always unessesary and they tend to be much worse wounds than a bit of natural tearing would have been. My advise would be to go back to your doctor and tell him or her about how tender it still is, that is not normal. Maybe you could see some kind of specialist for it. In the short term, use ice packs, sitz baths, hemmoroid cream (with yor Doctor's approval), and when you use the toilet don't wipe with toilet paper, it is abrasive, use a water bottle to squirt water on yourself to clean up, then gently pat dry with a bit of toilet paper. If the tenderness persits you should really seek medical help and don't give up unitl you find someone who can really help you restore function and sensation so you feel normal again. You can also try gently massaging the scar tissure after the incision has totally healed, that will reduce the ammount of scar tissue and restore elastcity, and it wil get you used to non-painful sensations in that area again. When you finally feel ready for sex again be careful and use plenty of lubricant, if you are breastfeeding you can have pretty bad dryness and you will need a good quality water based lubricant. Good luck, I hope you feel better soon!
And for anyone reading this who has not had a baby yet or an episiotomy, DONT LET THE DOCTOR DO IT! JUST SAY NO TO EPISIOTOMIES! They are not nessesary, I have had two babies without ever getting cut, with my first the doctor wanted to cut me and I told him not to, I was very adamant that I would rather tear naturally, I ended up with a very tiny 1 centimeter tear that did not even need a stitch, it would have been a much bigger cut if he had done the episiotomy. With my second I didn't tear at all. My midwife told me that women who have an episiotomy are much more likely to get an infection afterwards and the next time they have a baby they will tear right where the episiotomy scar is because scar tissue will never be as strong as intact skin. Itis importnat also to not lay flat on your back when giving birth, this is the worse position you can possible be in as far as the risk of tearing, if you have an epidural and can't move then that makes it harder, but you should still be able to deliver sidelying with support and that will reduce the chance of tears.