How do I start the conversation. What should I say to her. Should I bring up the fact that I don't approve of how this situation happened, but am dealing with it in a mature way and I care for the child. The reason he now wants me to meet the baby mama is because he wants to get married next year and thinks it should happen. He also wants to prove there is nothing else between them. I'm open to the idea but not sure what I should say. The child spends every weekend with me and him, because of shared custody and we live together.

Since you will be, and have basically been, a step-mother to the child, simply focus on the child and how much you care for her. You can comment on how verbal she is becoming, what a fun age she is, etc. if you feel it necessary to start a conversation. If she happens to bring up the past, maybe even offers an apology (not likely, but possible), accept her apology but let her know that your focus is on the well-being of little "Sarah" and out of respect for yourself, your soon-to-be husband and the child. Your actions will show that you are handling it in a mature way, no need to mention it. Who knows, in time you may warm up to her, but for now you can keep it civil and polite.

I think this is a case where you put your issues aside for the good of the child. You are allowed to express yourself, CALMLY, but be very clear about your willingness to move beyond the past and put the child first.

I hope you have resolved your feeling for this female though. Then you can handle this maturely, and not emotionally. You don't have to be chat buddies or even friends, but have some level of understanding... for the good of the child.

You may never like her for the past, but if you have forgiven your fellow for what he did then forgive her too, and never let the child suffer for adult mistakes.

First, I see no reason you need to meet the other women. You seem to exchange the baby without meeting her for two years. But if you do, You talk about the weather, you talk about how wonderful the baby is. You do not make any judgements, you do not really say much. This meeting,should be short, more for the purpose, of the baby mother knowing who is watching the child.