Mia, I relapsed while I was dating someone new too. It wasn't the first thing for me but it kept the ball rolling. It took me a year and a half to get sober again and the relationship didn't work to boot... but I don't regret it because now I know. The next time I'm dating I'll know exactly why I can't have a glass of wine. And I won't.
It sucks but it's not a waste. As long as you're still trying it's all part of the journey. You can get sober again. You need to figure out how to get the first week, then the first 30 days, etc... step by step. But you can do it.