What's the problem, Rachel? What do you mean by deal with it? Sounds unselfish, to me, that you gave permission to your son to babysit her baby. Clearly that tells that you are reasonable. Perhaps nothing more to do, other than staying cordial. Funny thing is that the work is on your son now; he has to change the diapers and all, mercy. :-) Maybe it is that I'm missing an important part of the history between you and the new girlfriend. Only to see more of what to say I need more of what your thoughts are for her and the ex. Rest easy for now.

I have never met her

But the situation between me and my ex husband is about as bad as it could be

I don't think there is anything to do. Are you not wanting him to babysit?

..,oh, I see. I can see how you think. And I'm so sorry that things are bad with the ex. How in the world did you get past giving permission to your son to babysit at your apartment though? I still think that you are not selfish, Rachel, and it is good of you to allow her in to the place, and in the company of your son. Let us know how it all goes. I'd just keep conversation to a minimal small talk with her. And I'd look for the better of who you are as compared to her; this way that green-eyed monster stays at bay. Not to say that you are most likely full of high self-esteem anyway. :-) No matter what, keep your spirit up!

Thanks, no I think it’s great for my son to babysit and I’m definitely not jealous

Okay- if you know how to deal with it- because your saying its great for your son to babysit then it is all good.
Best of luck-

I just wanted to know how to deal with meeting the girlfriend

Just say hey nice to meet you and then the topic changes to babysitting............ You got it girl take care
you will be fine- its your place your in charge let her see the great thing he lost. Best of luck.As long
as you are centered and as long as your Son is comfortable and hes in a good place etc-its all good
your good : )Hugs Cheers for you.

Another problem is that I’m afraid my ex husband will use this situation to make up more lies about me. Just a few days ago, I attempted a friendly interaction with his brother’s ex girlfriend because she is the mother of my sons cousins that he was with, it went really well between me and her, but then my ex husband made up all kinds of lies and accused me of harassing her

Rachel, I'm glad that you are looking way ahead. I thought the same thing about what could happen in the future. With the possibility of you exchanging stories of your life with him to the new girl, the facts about his character are really at risk of being exposed, and he may take the opportunity to twist what you know as the truth to lies in favor of his own purposes. And if at any time the new girlfriend appears as getting along better with you than him, or when she sees something in you that is opposed to what the ex sees in you, then it could be a chance for him to run interference and cover his own tail. Smart of you to think ahead and do be prepared for what is to come. You seem as a friendly person by how you express yourself, and I can tell that most likely the ex attempted to use you like a doormat. I've got a sister that is used in that way. Her husband is so mean, bossy and tricky. And if it helps for you to know this: I don't think for one moment that your brother-in-law's ex girlfriend believes any lies about you...you just don't appear as a dishonest person to me. The ex is an insecure type. Just overlook him for now and proceed as if nothing is suspicious, because if he senses that you are on to him, then the idea of hurting you grows out of him even further. Just ignore the thoughts until something comes up, which you will then have to figure an aggressive move in response to his actions.

That's not how you should of first met the ex's girlfriend. But, if you agreed to your son babysitting knowing what you know, then hard to back out now. Next time see her ( if you have to), at a more neutral location.

Thank you so much, that does help that you think that about his brothers ex, I felt so bad when he said what he did about his brothers ex girlfriend, I couldn’t stop crying actually, the thing is , all I talked about was the kids, not him, but he thinks it’s all about him and accused me of ridiculous things. Thanks, I never thought about his new girlfriend or meeting her, until my son said that she was asking him to babysit, which he was really excited about and I didn’t want to tell him he couldn’t do it, it was so sweet

And you are also right about him treating me like a doormat, he always has