Yup cognitive dissonance is alive and well! I'm hyper aware of it with my choices around food at the moment. I have started to think that my sudden physical distaste of meat is actually something driven by my unconscious mind pushing me to resolve some of this. I find it fascinating to attempt to pull apart my own mind like this! I was always able to say, with apparently absolute clarity, "it's OK because we're designed to eat meat", "the animals have been bred specifically for meat", and other such reasoning. The words of non-meat-eaters were water off a duck's back, largely because they're often very ranty, or inaccurate, or dismissive, or even abusive... but mainly because I was programmed to do what I had been doing, it was the normal, it was part of who I was, and I had no reason to change. Change is hard!
I'm thinking that what happened is that by studying more and more behaviour, and becoming more empathetic to dogs, it made me realise the breadth of emotion that exists across all animals. I didn't realise this at the time, but it's there with me now. If I try a tiny bit of meat now, such as when I'm cooking J's meals and I need to test for flavour, it's that thought that makes it unpalatable to me, even though that's not how it started.
And now... well, I still have a lot going on. For example, I'm still eating fish. I think that will likely change in the future, too. It's easy to think that fish aren't as important as mammals, because they are so different, but I watched a video a few weeks back which was demonstrating line-fishing from a boat. It was put out as a "wow, this is amazing!" sort of video, with the sheer numbers of fish they were catching, but all I could think was that those fish that were flopping around on deck were dying in fear, and that is not right. BUT, I am not ready to take that step yet, because Change Is Hard. Same with dairy. I know that by consuming dairy, I am complicit in keeping sentient animals in horrible conditions. When I do so much to enrich the lives of the animals living in my house by ensuring they're mentally and physically stimulated as individuals, that they live without fear and pain, that they are happy and fulfilled, how can I turn my back on all those hundreds of thousands of animals who are confined for life, without enrichment of any sort, without any consideration of their mental state and individuality, just so I can have cheese in my sandwich? One reason: cognitive dissonance.
I'll take it one step farther. I would never feed my dogs a vegan diet because - no. So, I will continue to support the meat trade by keeping dogs. If I were to completely shed myself of CD, I would have to stop owning dogs. And pretty much living life, if we're honest!
The truth is, that there is no one right answer. Even if I were to give up on all products tied to the meat industry, how far do I go in ensuring there are no paths back to it? Honestly, I don't have the time or energy to ensure that no bone has been used in the fertilisers in which my veg have been grown. That the carbon footprint isn't huge. That the synthetic materials I might choose over leather are better for the environment in all ways. That they don't support slave labour or poverty. It's all just too much. People pointing these things out to me is more likely to send me scurrying back into my hole of doing what I've always done, rather than pulling me over to their way of thinking. It's truly and utterly exhausting.
It's really no wonder that, when people who are new to "a thing" are told "this is the right way", they take that advice from people who have experience. It's human nature to do so. And once that becomes a "thing they do", it's hard for them to change. This goes for the people who are doing the telling, too. We should not judge those people harshly. After all, when you are told you are WRONG for eating meat, does it make you change your mind? Does anything I've said above change your mind about it? It's really, really unlikely, because it's a Thing You Do. It doesn't mean that you've not considered it - I had, many times previously, and I had plenty of reasons as to why it was OK to continue. So I don't expect (or want) to change anyone's mind about eating meat, especially when I'm still muddling through the issues myself. But, in the same vein as this discussion of what is wrong, and cruel, think about all those people who believe YOU are wrong and cruel for the things you do to animals. I'm not one of them, I hasten to add, but you can see the parallels, I hope.
These things they do don't make them horrible people, in the same way that you're not a horrible person for eating meat, driving a diesel car, using a plastic bag, squashing a bug... we all do the Things We Do until we are ready to change, if that ever happens, and no amount of condemnation is going to change the majority of people's behaviour.