I’ll jump on the bandwagon and say just go for it! You are definitely a bit younger than a lot of us here, so I don’t see that as an issue, unless you are ill and have mobility problems.
However, you say it would cost a lot of time and money to go - is that a major issue? I’d be happy with driving, as coolgran suggests - yes, there’s a cost to that but if your DH had driven, the cost would be the same, as would be the time involved.
As another poster would say, it’s time to get your big girls pants on and strike out on your own.
This could be your last chance to see your cousin.
Good luck.