I have a feeling that I can't fight.
Have you tried not thinking about the feeling so that you won't feel it?
I tried to do that, but I obviously failed because I still feel this way.
You should control your emotions and not let it control you. You can go on therapy or do other resourceful things to take your mind off it.
This feeling is really hurting me, but in a way it feels good.
While it feels good right now, eventually this sort of damage will hurt you and so you should worry about it now. Taking care of this as soon as possible may help you. Try seeing a therapist or something for these abrupt feelings.