It did not even come in an envelope either. So, for every curious postie to read. I know mine is decent, and will not do that. But fuck it, lots of people will get this, lots of people in small villages, and some of those villages will have very nosy posties.
So, pissed off that my address got used for this.
And pissed off that they did not want to wrap an envelope around it on top of that.
Is there a Better Business Bureau where you live? If so, complain to them. 
I've written a formal complaint to the agency where my address came from. It's a support agency. With the request to send this complaint to the dating-site agency too. (It was only possible to mail the dating site when giving a massive amount of personal details, and since privacy was the issue to start with, I did not want to do that)
I've made it a triple complaint.
First, where did the right come from to use my address for this shit.
Second, why no envelope around it. Making it visible for every postie on what addresses "psychosocial and psychiatric vulnerable people" live is putting people at risk. Abuse and theft and such are not unheard of, lately, when it comes to the mail.
Third, by sending it out on Feb 14 they are kinda implying that the receiver is a sorry sod who probably is without a date or friendship, because of their diagnosis.
I signed my mail with my name, and then the qualification "psychosocial and psychiatric vulnerable person" from the place where I live.
I got a reply that my mail has been received and sent on to the people responsible for this campaign.
Will see what further reactions I will get.
ponds from now on.