Debts/co-habiting/Marrying

Hello,
I have some personal debts from my previous relationship.

Now myself and my new partner want to live together and eventually marry.

My questions are:

What is the law concerning my personal debts? What I mean is that most debts are in my name and there are two that are joint debts with my previous partner.
I want to know what security has my new partner got from these debts? My understanding is that she is protected from these as in they are in my name and she cannot be brought into this matter?

Also what protection can my new partner have from the creditors in that they will not approach her?

I can only assume that we create an arrangement stating that what is mine is my responsibility, etc....

Thanks in advance !!!!!