Never be ashamed of what you love. If it harms no one and gives you joy, if it lifts your spirits and provides a modicum of comfort when you're feeling at your lowest, and if it especially
helps when you go out and seek people to identify with over the mutual commonality of what makes you happy... never be ashamed.
Are you a furry? Do you have such bizarre fetishes as "slime girls" or inflation (and may even fancy some furry porn)? Do you feel like you're under scrutiny for liking the Star Wars prequels and any associated media (i.e. The Clone Wars) without any irony whatsoever?
People who judge you as a human being based on something harmless and trivial you happen to take some joy in? Pardon my French, but they're douchebags, the sort of douchebags who want to feel any measure of superiority over their fellow man and so go for some real cheap shots. Do not take a single word of what they say with even the smallest grain of salt.
But that being said, if you come across someone who has a legitimate grievance or otherwise may not understand why you like this or that, and may even have a critique in mind, don't shy away or respond defensively. Instead, see it as an opening for a discourse, for a dialogue.
For example, I have quite a number of friends who still like Sonic the Hedgehog despite all the horrible games that franchise has produced over recent years. They even like some of those horrible games. If I were to judge them based on that, I'd be quite a dick. Who the hell am I to say what they can't or can enjoy? What authority do I have to determine what a person should or shouldn't like?
Do I like the franchise of a now hopelessly anachronistic "totally radical" icon of the 90's whose only contributions to modern gaming have been so infamous they been deemed as gamer culture's equivalent to famously awful films like The Room, Birdemic and Batman & Robin? Well, as you can see, no. But there are people who do, and I don't have to like the franchise to respect that they do.
I like Friendship is Magic. But as you've read, you know I've been critical of the show. While one should never be ashamed of what they like, always - always be prepared to acknowledge that their might be a few glaring flaws with what you fancy, be it Sonic the Hedgehog or My Little Pony.
Still, if you're being insulted for what you love, you are not obligated to justify that love. Tell that ass to get lost.
This, my friends, applies to everything from fanfiction writing to personal kinks and fetishes. Never, ever, feel awful about any of 'em.