I was going to say "no," because I am a generally happy person...now. I've suffered from severe clinical depression in the past, been through some really rough crap, and have a lot of potential stresses and challenges in everyday life. There are things in my reality that others can't understand how I can tolerate them, and there's plenty that has come close to breaking my sanity altogether.
Thinking about it, I am happy because I work hard at being so -- I know what kind of environment will nurture happiness for me, I know what work fulfills me, and I know that I need a steady diet of relaxation and positive energy. It really is a lot of work to create this type of environment and maintain it, and it takes constant vigilance to refocus away from things that will steal my contentment, and to release the urge to try to control people or situations. It's also a bit of work to stop and review what's great, what's going right, and what I'm blessed to have in my life, which is so essential to maintaining happiness. So...yes, I suppose it is difficult to be happy, but I still am most of the time. I love my life, I just know what steps I need to take to maintain my well-being. It takes a lot of introspection and a lot of structuring -- or does in my case, at least -- but I'm also of the opinion that nothing worth having comes easy.