"You don't start out writing good stuff. You start out writing crap and thinking it's good stuff, and then gradually you get better at it. That's why I say one of the most valuable traits is persistence."
Writing is hard. If anyone says anything different then I want what they're having. But, despite the (occasional) hard moments, you write. You make the time to sit at the computer to type those words day after day. You edit and rewrite and query. You go through the rainbow of emotions that accompany it.
You smile at requests. You file away the rejections. You shelve manuscripts you love. You use scenes/dialogue/characters from old manuscripts and recycle them into new ones. You write scenes and dialogue on scraps of paper (or envelopes. I've lost count of the number of envelopes I've scribbled on). You balance your real life with your fictional ones. You write. You persist. That is the important thing.
Never give up. Never surrender.
You are a writer.