For me it has changed a lot with age and partner. I'm 29 too.
I had an incredibly high libido in my teens (think craving sex multiple times a day for years). this was with a few casual and one long term (abusive) partner.
I then met my second long term partner aged 20 and for the first year my sex drive was high, but suddenly, a year later, it just died. At the time I had no idea what it was. It caused huge tension and strain in our relationship. He was lovely in so many ways, we tried so many things to make it better, but the more we tried to force it, the worse it got. That (sexless) relationship lasted 7 years - most of my 20s. We eventually parted ways for a number of reasons, sex being high on that list for him - less so for me because good sex was just a distant memory for me and I, like you, was convinced I just wan't that fussed with it. I lamented the fact that the sex of my teens was gone forever, but if sex was only fun with bad boys, then I was willing to go without.
Funnily enough, it didn't take long for me to realise that that was a load of bollocks. It took one (hilarious) fling to realise definitively that my sex life wasn't dead after all - it just couldn't be bothered with my ex but was now back and raring to go.
I met another guy shortly after that, and not only was the sexual chemistry was tantalising, he was nice too. It's only just coming up to a year, so it might be too early to tell, but he is kind, funny and smart, and I also want to rip the clothes off him every time I see him. Somehow I don't think this one will go the was of the last one.
I am so glad I didn't (accidentally) end up having terrible sex for the rest of my life. I wake up every day over the moon that I can feel sexual desire every day. I probably sound a bit bonkers, but its such a huge part of my life, I feel like I've found a long-lost piece of myself.
I can now look back with the clarity of hindsight and see the things that weren't quite right in my second (sex-starved) relationship, even though at the time everything seemed fine. It wasn't that I was broken forever, just that relationship was, but it was too subtle for either of us to see. I didn't leave for the purpose of finding better, but I'm so glad I did.