I was thinking about one of my mental stumbling blocks today: the feeling that I don't have enough experience with LTRs to do well in an LTR. But then I stopped to do the math, and realized no one has that experience.

Let's say an LTR is at minimum 6 months. That should be long enough to say that you'll probably have some sort of actual relationship that you've worked out rather than just using 'relationship' as a fancy word for repeat sex. Combine that with breakup recovery time and new person discovery time and your minimum time between the start of successive LTRs is at least a year with the average probably closer to a year and a half or more.

So how many LTRs is it even possible to have experienced? Most people I know didn't start doing anything they considered a relationship until they were at least 15 or 16. Teen relationships barely count to begin with since both parties are usually too immature to respond as adults would.

That means at the very most a person who's 25 or 30 could possibly have had only 5 or 10 real LTRs--probably much fewer because this isn't the kind of thing people try to maximize. With the difference between the way different people react in relationships, we can pretty comfortably say that no young person has a lot of experience in LTRs. At best they've figured out the things that work/don't work for a small handful of people that they've dated.

TL;DR Do your best, but don't worry about comparing your experience to that of others. No one is really that experienced outside of the narrow domain of their own few relationships.