Hi tatave,
I had a different, but equally debilitating, issue a number of years ago (10 or so now). I was flying a light single in marginal VFR. The engine began sputtering quite badly and I was certain in my mind the engine was failing. I landed after reaching the closest airport 20 minutes away. Maintenance had a look at the airplane and they figured it was very bad carburettor icing.
At the time I had 80 to 100 hours total time. Even though I could logically explain in my mind what happened, I was damned near terrified to go flying. Any out of place sound had me setting up for best glide and a furious search for a place to let down. My stomach would turn with the engine and I (figuratively) kissed the ground every time I landed. It was a number of years later and almost four hundred hours that I finally found I had stopped worrying every time I went flying that the engine was going to quit. I almost left flying because of it and even then it stopped me from switching from a part-time and full time pilot once I had my CPL. My career definitely took a hit.
My point, I guess, is that it finally just went away. I can't tell you what happened or when it happened but I just realized one day that I had gone a couple of flights without thinking much about the engine. It was probably just a lot of exposure in a short amount of time, but it saved my career. It was a horrible experience, but I now look back on it and realized, much like you have, that I was not enjoying flying at all. I was paying a lot of money, and then got paid a little bit of money, to be unhappy...kind of like a bad marriage.
I hope that you find a bit of exposure cures it, but sometimes just getting it off your chest also helps. Feel free to PM me and I can expand on what happened to me.