When I started being lacto-ovo two years ago, my reasons had to do with health and personal preference. As I became more aware of animal cruelty issues, I changed my "story" and started to tell people I was vegetarian because of animal cruelty--and people (not even veggie people) called me out for eating eggs and dairy since those are cruel industries, too. Finally I started to agree with my critics and I'm trying veganism. The biggest surprise so far? How easy it is.
If somebody gives you a hard time about eating dairy products and eggs, remind them that animal products are all around us, used, for example, in the production of the rubber tires that carry a shipment of vegan food. (That example comes from veganoutreach.org's excellent Q&A paper on the aims and practicalities of veganism). Everyone is probably going to use some animal products, whether intentionally or not. Your lifestyle choice (the ovo-lacto diet) is an admirable one. You can always change later if you feel you're not doing enough.