This is very much based on personal experience, and I am sure there are lots of ways to get in to being vegan, but knowing failed vegans, current vegans and people who go on about how hard it must be, I have come to the conclusion that dairy is one of the most significant factors in being vegan.
For me personally, I didn’t have dairy for years and years before I went vegan, for health reasons. It might have been part of the reason that I didn’t go veggie – no meat and no dairy is pretty close to being vegan and I assumed it would be very hard. Now that I am vegan, I think that the years of experience not having dairy help me a lot. I am used to all the alternatives, know what to use instead and what things to avoid that you might not realise straight away. And getting used to these things was quite easy, because when I was eating meat I could easily make a meal centred around chicken, lamb or beef and no-one would really care that there was cheese on the table or yoghurt in the curry (sorry, that was the best example I could think of).
By comparison, not having meat is very easy. Few things do not have a meat substitute if it is imaginable at all; veggie pies, sausages, burgers, nut roasts etc. – the list goes on. Psychologically it feels like a bigger step (to me at least) but in reality it is very very well catered for (in the UK at least). And I really didn’t notice or even think about not having dairy – at no point did it occur to me that it might be convenient to use anything dairy based.
However, I think (and obviously this can only be my opinion) that if someone starts by going vegetarian, it is very easy to end up being reliant on dairy. Obviously dairy products will probably already be a regular feature in most people’s cooking, even to the extent that one could probably make a lot of dishes featuring some sort of dairy product as a central part of the meal. And of course, it is a ready-made replacement for meat in terms of its universal appeal, protein content and the ability to have a lot of it. There are other specific circumstances, such as a lot of sweet products containing milk, the creaminess of meals and milkshakes. And once you become so reliant on something it can be at least a huge psychological barrier, even if not a real one, to finding alternatives.
On the flip-side, by not having dairy you get used to a whole host of dairy free meals and cooking, and as already stated, many of these have alternatives that are exactly the same (bar their meat content). So practically no adjustment is needed to start cooking the new versions of all your favourite dishes.
Lastly, a quick comment on the egg situation – the only things that are significant for me for eggs were omelettes and cakes. I don’t have that much of a sweet tooth, and how many omelettes can you really eat!!
So, I genuinely think that if you are having an issue with going vegan, focus on the dairy. Maybe cut that out before the eggs (I imagine most people wouldn’t want to go back to meat), and really try a whole range of alternatives and new meals and veget