There are as many paths to victory as there are players, just as there are as many reasons to play. At the end of the day, if you're not into it you won't stick with the character/game if you can't find a reason to. For some, it's simply about the competition and can look at a tier list, pick the S+ character and call it a game. For others, it's "This character rox" or "I have fun playing this character". More good reasons to pick a character and play a game. What I'm saying is, before you can do anything else, define for yourself what "fun" and "enjoyment" mean to YOU.
Next, I can totally relate to not wanting to lose, but the sad reality is, you're going to; even with Kabal. Learn to deal or quit competing. If your wins are hollow and your losses are making you extra salty, it's time to take a look at this. What I see many players doing is ignoring what Capcom players call "Character Symmetry". I mean this slightly differently than they do however. I'm talking about picking the perfect character for YOU and how you like to play. Let's take REO as an example. He is knowledgeable enough that he can post tech vids on every character in the game (not sure if he has but I'm sure he could if he felt like it) but he never strays from Kabal and has taken the character to places that I'm not sure anyone even knew existed. Why can he do this? Kabal meets his "Character Symmetry" requirements.
As another example from the other end of the scale, I myself have had internal strife over this very topic. I struggle so much with Sonya and the perils of playing on a stick that I thought maybe my character loyalty may have been misplaced in this game. So I tried Skarlet. Felt very familliar due to the similarities between Skarlet and Sonya but Skarlet feeling overall faster than Sonya. I would take my Broke-assed Skarlet to locals and while I still wasn't logging wins, I was getting much closer with a character I still had to pull up the movelist for than the one I had trained for months. At the end of the day, Skarlet just didn't "feel right" and I found myself back in the lab with Sonya.
Had another crisis of faith about my ability to even play a "rushdown" character, so I went to Freddy. I figured that if I could sit back and control the pace of the match through zoning, life would be good. I started playing Freddy like Sonya and well, I'm sure you can see where this is going.
My suggestion to you is, grab Cyber Sub, have fun, train him up and the wins will come. I would even dare to say that you won't even notice how fast you are levelling up and getting the wins because you'll be enjoying yourself and feeling more self-satisfied that you won't even notice the effort that you are putting in simply because you are doing what you WANT to do rather than what others TELL you what to do.