We can't change the past, but we can change the future, and learn from our mistakes we've made in the past.
I was in the same boat. When I got my DUI, I was given the gift of having the meetings forced upon me. At that time, I wasn't ready to commit to anything, but took a lot away from them. Kept on going for a while after my court-ordered ones were done. It kept me "in-check" for a while, but as the story always seems to go, I eventually stopped going and went back to dumba** drinking again. If nothing else, being forced to attend those meetings, it instilled the knowledge of what AA was like... Something I actually liked.
Fast forward about 9 years, and I found myself bordering on another DUI. It's a miracle there wasn't another in that 9 years. But I started scaring even myself... Leaving the bar lit up in my new (to me) Tahoe, taking the long way home so I could hit a straight stretch, and opening it up. Any responsibility I'd been working up to flew out the window once I had that first drink. It wasn't something new for me... It's something that's been going on for over half my life.
But, back on topic, go ahead and get a sponsor. You're not glued to them for life... You can get a temp sponsor and change down the road or have multiples even. But, as with going to the meetings, having the sponsor has the exact same benefits. I can only speak for myself, but if I hadn't gotten a sponsor and started working the steps, I'd put money on it that I never would've picked up that 1-month chip and I'd be back to joy-riding.