You can adjust your privacy settings so that only "friends" can send you messages and you can also stop yourself from appearing on the language partner search page. Probably worth doing if you haven't already.

It's not worth if you want to about leave Italki because of you received that kind of messages. So far, I think Italki is the best website for learning new language. Else every things have the negative side and positive side. So, for me I don't take that thing as a big deal. 

Unfortunately, that's a daily occurence on italki. Once in a while I receive some weird messages from both women and men trying to flirt and often receive messages from Mormons who want me to know their 'truth'. 

Yes, it happend from time to time but I will not stop using it just because of that. Honestly speaking, if you go to any kind of English traning websites, it happends all the time. I think italki has many more serious language partners here.

Probably dating even happens on the spaceships that the taxpayers dearly pay, but they keep us in the [sidereal] darkness, and that's ok for me, they will probably perform better the assigned tasks.