You haven’t mentioned a word about how your wife feels about the marriage.
From the little info. you gave, esp. if she has doubts as well, I would definitely recommend IF POSSIBLE you discuss birth control with her and your rabbi, if she’s not on b.c. yet. Sorry if I’m being too personal, but kids should not suffer for parents mistakes.
Once that’s taken care of, I can only echo what other posters have said. Do your best to work on YOURSELF and your marriage.
A marriage working out usually boils down to middos of both parties, so that’s something to bear in mind.
Question to ponder (you don’t have to answer): are you a perfectionist by nature, or have you truly gotten the short end of the stick?
And last but not least, and I might get yelled at for this, but since you mentioned not making headway in therapy, be aware that some therapists may design this so they can profit from more hours billed. So maybe change therapists or find a mentor (not a family member) or Rabbi that will counsel you at no charge. (you can always tip later if you feel he’s worth it, not necessarily based on the hours spent.)