So I've been married to Sam for a while but wanted to see the different cut scenes for the other singles. I have Sebastian at 10 hearts plus bouquet but his 10 heart cut scene hasn't activated days after giving him the bouquet. Can you only see all the singles cut scenes if you're not yet married? (I've no intention of cheating on Sam, was going to turn everyone down at their cut scenes. I'm a heart breaker)
You can still see the events. Check the wiki if you want to spoil yourself, otherwise, just wait patiently.
Try seeing what you need to do to unlock the cutscene - some places you may see it without spoiling it - then you can just trigger them yourself.
You can't turn down everyone, just so you know, some characters regardless of what you choose may proceed to kissing regardless of what option you pick.