Dating sites are an extremely hard business to be in.

On a traditional (social) network, whether that'd be Facebook, the railroad or the Bloomberg Terminal, you have the network effect. The more users you get, the more interesting the network becomes, which means yet more users want to join. This is a positive feedback loop.

The entire point of a dating site is to find somebody to leave that site with. Statistically speaking (and at that scale, statistics is the only thing that matters), attractive users[1] are more likely to find a match and leave, while unattractive users are likely to stay (or come back) and keep looking. As time goes on, the fraction of unattractive users will keep increasing. You can fix this with enough growth, but exponential growth can't go on forever due to population size constraints. And once you get into that state, your growth will be constrained further, which just puts you onto a downward slide into hell.

And then there's the question of revenue. It's hard to scalably do deals where the user must pay you when they find a relationship on the site (like the matchmaking services of old used to do), so subscriptions or one-time fees are your only options. Neither of them are great, subscriptions encourage you to keep users on the site (which puts your goal opposite to what the users want), one-time fees work against the network effect and constrain growth.

[1] By "attractiveness", I mean something much wider than just visual / physical attractiveness. An ability to enter and maintain a successful long-term relationship in general.