Have I already found my soulmate

I’m female Aries Rat, March 26, 1984 and he is male Sagittarius Ox, December 6,1985. We met December of last year on a dating site. He and his current gf who he just became official with three months ago are in an open relationship, she is Virgo Ox (1985). He knows I’m not interested in that but we can’t deny that there is something special about us. Is he my soulmate and has missed out on me or is there someone better suited for me yet to come into my life? And if so, when? I’m getting old (I don’t look it but I’d still like to settle and start a family soon).