Well first of all you should have been honest with your IP from day one with regard to your exact circumstances. If you and your fiancee are living together and are to be married, then this should be properly reflected within your IVA proposal.
But I genuinely feel that you are now beating yourself up about something that is not a problem. Although your IVA should disclose both incomes, and then a sharing percentage of joint expenditure based upon income ratios, this does not mean that your partner's surplus income should be included in your offer to your creditors. Indeed it should not.
I am sure that your partner will understand why this has to happen, and will be supportive. And I am disturbed that the events of today have stopped you feeling like seeing your son. There are things that a far more important than having a few debts, and your visits to see your son are up there pretty high.
Please don't feel stupid. Perhaps some more in depth discussion with your IP from day one might have identified this issue at a much earlier stage. I always question "tenants" as to whether they are in personal relationships with their "landlords". This prevents these issues becoming embarrassing at a later stage.
You are worrying about something that is easily resolved. Go and take that puppy to see your son tonight!!!
Regards, Melanie Giles, Insolvency Practitioner for over 20 years.
For further details contact me at http://www.melaniegiles.com
and view my IVA blog at: http://melaniegiles.blogs.iva.co.uk