I am not her father but have been with there mother for ten years pretty much raised her but now she does what she wants an does not follow any house rules very stressed ready to walk out I can not deal with the disrepect

I would have a talk with your partner and tell her just how you feel.
You two need to agree on the rules and support each other in the decision you make.

Relationships need honest communication to succeed ,
It is time to get this going.

If she cares for you she will listen.

I wish you well.

You're the adult she's the child.

She needs a lot of support right now,as do you and your wife.

If you and your wife can agree to stick together to enforce the rules of the house,what ever the child says,stick together! A united front.

No doubt the 15 year old THINKS she has all the answers,time she knows there's a new sherrif in town and things are going to change.

Be firm and fair.

If she needs to be led by the hand,do that.

At 15 and pregnant she's going through a lot,hormone changes,body changes,it's a scary time for a grown women,double for a teen.

Have you considered councilling for her and/or your family?

Make sure you and your wife have time together,date night!

Get a babysitter for the 15 year old,someone who won't take any crap and you know will keep order while you and your wife have a break.

Be consistent! If you make a rule stick to it.

One more thing,she's 15 and pregnant,also under age,you don't give any details of the father,but having sex with a minor is against the law.

I wish you the best of luck,it's a tough situation.

Well, I think you should just make it clear to her who's the boss: if she's pregnant and living under your roof tell her that it's a privelidge that she's living there so it's your house your rules.