Is it possible for them to get engaged or married?
It seems like I’ve been stuck in dating mode, doing the same thing, forever now.
And is it possible to date more than one person at once? 
im afraid the answer is no in both cases ;(
Would be nice if you get actually get engaged and married by aggressively and successfully dating, with perhaps some very minor benefit, as a result. Then, of course, if you didn’t keep the relatoinship up with more dating, it could sour and end in divorce, with a lot of personal trauma.