Does anyone ever call a monogamous married couple who have sex several times a day sex addicts? No. It's only called addition when people are hooking up with different partners, which has nothing to do with the frequency or appetite for sex. Everything is called an addiction, sometimes with a lack of thought. Same with food. Even if someone is on a healthy and reasonable diet, they still crave food everyday, several times a days. It could be called an addiction, but it's necessary for sustained life. When it involves too many calories and the person doesn't exercise then it's called addiction. But doing things in an unhealthy manner is not the definition of addiction, it's the definition of gluttony and unsafe sex.
I'm addicted to breathing and hope to stay that way for as long as possible.