Friends with benefits

Kyrstyn
Okay so me and a co worker Seth have been friends with benefits for almost a year. Within this year we took a little break about two months because i decided to call things off because he started dating someone else yet didn't tell me because  he wasn't willing to end what he said "was a working relationship for one that would fail" well we started things back up again when we started working again because we work at a seasonal job. Well he knows that I have deep feelings for him and we were both each other's first. Almost everyone we work with including his mom agrees that they think we're dating and that they can see us going far in our relationship to the point where they have called his mom my mother in law. They are solely getting this idea by how we act towards each other. Also I should add that for awhile now he has even made made comments about us having kids and getting married. Along with how he is very much like his dad to the extent that his dad did the same thing to his mom. His dad Bruce kept him and Lisa seths mom at a friends with benefits for multiple years until Lisa finally sat down and told him that unless things changed she would leave him. However I am still unable to get Seth to agree that we are dating because he claims he only sees me as a friend when his actions say other wise. Should I keep trying to get a relationship out of this or should I just call it quites?