How can i trust people with my kid?

Beautiful little girl, and you do look much older than 17. Seems to me like you have your priorities straight and to you and your life your daughter comes first and as long as your girlfriend knows that, you should be good/ But having that said don't rush nothing man, if the woman wants to be part of you and your daughters life, make her prove it, date, build a relationship and then go from there. As for her loving her own daughter more than yours, there is always a unconditional love from a woman to a child that can never be replicated so off course she will never fully love another like her own, but to be there from that age that your daughter is and to raise her over the years she will love that child like her own.