In this YES that guy was wrong.
But girls like you do mistakes too. You knew he had previous relations, never guaranteed you the clear relations with you.
It is you who neglected these and yet preceeded because you liked him, you liked his things, deeds, whatever it is, you liked it and hoped he will be with you always.
There r plenty good guys that are too much loyal. But things with them is girls never look up to those. Because girls always like to have some spicy, odd, macho, different relationships.
Guys are too good to fool girls.
Girls are too dumb to trust and give away everything they have.
Never be physical if you want to marry that person.
First get assurance, wedding, or parent meet. Then only think about proceeding ahead step by step.
Be physical only if you want to be physically involved. No other intentions.
If you have other intentions I would recommend not to get physical until there's fixed assurance.