What can I do to stop the mother(joint custody alternate) from bringing her 21yr old daughter from coming to the drp off/pck up?

You can petition the court, but i strongly suggest you speak to counsel.

How much visitation do I give my ex for a 15 month old

The more you can bring in people who love your daughter, the better it is for her.

Spouse's social security benefits

Since you are not married for 10 years, should you get divorced before that time you will lose your ability to collect then.

Divorce from overseas

If either one of you is domiciled in NY for a year before the divorce in many cases, NY should have jurisdiction over you. Please speak to an...

Do i have sufficient grounds to contest my non custodial parent status if the custodial parent is refusing to allow over nights?

You really need to speak to counsel regarding your case. Every case is different.

How can i get my ex's boyfriend off my back since he wants to interfere with the relationship with my children

You need to have a conversation with mom that this is inappropriate. If that does not work, you may need to petition the court for some relief, but...

You really need to speak to someone for more advice. Someone would need to review your case, and have a complete conversation.

Should I make a statement on my daughters father for violating our order of protection?

Please talk to your attorney to get more information.

Every case is different. Please schedule a consult with an attorney for more specific advice.

Is there an alcohol monitor program in new jersey to make sure that parent is not drinking during child visits?

I've never heard of such things existing. There is no alcohol monitoring bracelet for parenting.