Every vegan I've known has ended up the same way, their body starts to react negatively to the diet, they get sick, doctors tell them that they are low on some essential vitamin, they eat meat, it's the most delicious thing that they had an ages, they realize the entire vegan movement is a scam and a death cult.
The only people I know who don't have this happen to them, are rich celebrities who can afford all of these supplements.