Absolutely! What is the alternative belief?
To believe we live on a planet with (more than 6 Billion people) on it and yet (there is NOT a single person out there) that would make a suitable mate for us....etc Now that sounds "unbelievable"!
If that were the case it can only mean that an individual is either (too picky),has "unrealistic" expectations for human beings, or is very negative.
You have to keep your eyes and your heart open in order to find and receive love. The limitations we set for ourselves determines our possibilites. Being single or attached is a personal choice!