What is important to you?
3 years ago weight lifting and diet were my main priority.
Today, i'm just happy to feel the iron 3-4 days a week and lift weights half as heavy as i used to. my priority is now my business and then my girlfriend/family, with the gym coming in behind all of that. i still eat great, mainly because my girl cooks so well for me and i am still in a healthy eating mode. i lifted weights for about 10 years before i took a step back and realized there are better things in life than bodybuilding/powerlifting. i was self absorbed just like many and i only worried about myself, my diet, my training, my cycle and my resting periods. i look back and laugh sometimes but bodybuilding taught me how to be strict on myself and made me a more goal focused individual.
As far as marriage is concerned, it is NOT for everyone and i don't think anyone should get married just "because society says so". i think many people believe that they HAVE to get married but that is not true, i know many 40 year old single men who still train 5-6 days a week, but yet they still want more out of life.
One day you will meet someone who changes your perception on what "marriage" is all about. it's not about sharing bank accounts and tax breaks, it's about caring and support for someone you would give your life for, if you don't understand that and cannot comprehend that statement, then you should never even waste your time dating IMO.
People who are always alone usually lead very boring/depressing lives, at least from what i have seen.