harman - Just really wanted to reassure you that if they thought there was a prob with your parenting they wouldn't be referring you to therapy, but to social services. Therapists know (should know) that therapy should happen only with a certain amount of stability or resilience - if they thought you weren't coping and there was likely to be big upheaval (i.e. social services) they would be less likely to refer you for therapy. I'd try to take it as a compliment that they've recognised you have the strength inside to cope with an awful lot and that you have the insight, intelligence and bravery to confront your past through therapy.
I know there are scary stories like FL, but it doesn't sound like they are worried about you in that way. Like others said, ask them to outline their confidentiality policy too - when would they have to break it legally. Then you can be clear about what you do and don't say - gives you a bit of control back. I.e. they may only have to break confidentiality if you tell them that you are going to self-harm, or that your kids are in a risky situation.
So sorry you've had tons of crap to deal with and I hope you find someone to help shoulder a bit of it. Oh, and if you don't like your therapist, ask for another - cite 'therapeutic alliance' as the critical factor in therapy success and they should take you seriously!