I have been vegan for 5 years now. Nothing is more disgusting than meat to me. I am proud to be vegan, and love animals so much. I can never stand suffering of any animals. I even save spiders and put them outside instead of hurting them. I never have ANY desire to eat meat or dairy. BUT, there are places, ONLY with pastries, I sometimes have them, made with dairy and eggs. This problem happens once a year or twice a year. For example, a cheesecake from the Cheesecake Factory and Mexican sweet breads or Cuban Portos bakeries guava pastry. They have been a favorite of mine ever since I can remember. But can't eat them.
First of all: I always think it is better to be 98% vegan than not to care at all. Being a 100% vegan is almost impossible, cause I don't know all the ingredients a restaurant uses and have to trust them if they tell me they did not use butter for example.
If you eat once a year dairy or eggs you do so much for the environment and animals and that is great.
But I understand you feel not good about it- so I think good option is to cook or bake your favourites by yourself? There are tons of recipes in the Internet which copy all kind of meals from large brands-vegan style.
I personally find certain favorites hard to resist now that I am vegan.
But as mentioned above, I try not to get hung up on perfection because it is not the point.
We are all on our own path, and progress is the point, not perfection.
That said, you already know you are cheating, the question is, are you okay with it, and if not, what can you do about it? We all deal with it at some point, if we're being honest.
If you want to stop cheating, ask around. There are as many ways to stay vegan as there are people. Personally, I just don't go to the restarurants that have my old temptations, and if I absoultely have to, I'll eat a huge, fiber-rich meal beforhand so I'm not tempted. There are hundreds of other strategies though. Progress, not perfection.