Is hoping for love unrealistic?

My (27f) parents have been looking for a guy for me. I'm of the mindset that I'll marry if/when I am absolutely sure and have no doubts. You know the kind of thing where your heart is in it so even if you're scared you do it cause you're excited. I see a lot of people around me giving themselves a deadline, that by this time I want to be married. I just can't get myself to do that. I am sure I won't get married if my heart isn't in it, but sometimes I wonder am I being foolish. Is hoping for it foolish? And is getting married to a person that seems 'decent' good enough? Can you be happy like that? Am I being too demading?