Well, 2checkout is a merchant account. It's just a third party account. And for dating websites your options are very limited. You'll need to find a high risk processor and their rates are going to be much worse then 2checkout's.
It's an upgraded Paypal Service that works more like a true merchant account and gateway (but not quite as good). Customers can pay through your website like you were using a gateway. The costs are the same as an average merchant account.
Pay Pal also doesn't listen to a word you have to say about your case even if you have proof the customer committed fraud etc.
They even allowed a customer of mine to reverse the charge & then reverse the reversal & then months later reverse again claiming they never authorized the transaction when clearly all the while the customer knew exactly what they were doing.
This was on a so called "authorized" account & I trusted PP to do their job & screen people who had such an acct.
Even with a clean account & near perfect record, they treated me like I was a criminal & just took the customer's word no questions asked.