It sounds like you have decided to stick with him-& I think that is great! If you are not in any hurry to have him ready for a specific event, then take your time, especially since you do feel a connection with him. You’ve only had him 3 months-that really isn’t very long. I think you are on the right track having him checked (or perhaps re-checked?) by your vet. I stuck it out with my OTTB mare, & after many tears & frustration & scary rides, she & I have a connection & trust that I haven’t had with any previous horse. I think previous posters have given you lots of good advice; check saddle fit, check for pain, take it slow, & what Huckleberry said re: the Parelli’s…. Good Luck & don’t be so hard on yourself!