I've been a pescetarian for a year. Maybe try to reintroduce fish and, if it doesn't go against your religion, shellfish and see how that goes?
Idk why you chose to be a vegan/vegetarian but I chose to do so to not contribute to the demand for animals being processed as food (though, again, I eat fish and shellfish). I don't think I could go back now. I had a couple of bad injuries when I first dropped meat, but made the connection that I wasn't really getting much, if any, protein (would just eat bean and rice burritos, chile relano, etc.). Once I started ensuring to incorporate protein like fish and tofu and beyond/impossible meat, I have felt a lot stronger and healthier.
Good luck.