Are avocados bad for you? (really high in fat and cholesterol?)?

Hey guys, ever since I was a little girl I would love eating avocados and last summer I even took a class to learn how to make a killer guacamole! Anyways, I usually put avocados in my salad, sandwiches, and even use it as dip when I feel like it. My friend recently told me that avocados are really high in fat and cholesterol and that I should be careful eating them. Is this true? What do you guys think!?