In Gods plan of marriage, the sex act is the act that bonds two humans together forever. That is marriage! Any other ceremony is secondary.
If your holding back because it is a sin, then "if your not of Jewish decent" and a Gentile, then YOU have no sin because sin is transgression of the law that you were never forced to follow by God, only Religion and churches make you followers of law in our life as it applies to us today. I call them preachers or messengers of death.
Personally, I would give everything to go back to where you are now and wait for marriage, only because of the extrema affection you would have for that significant other in the future. Wait.