Options
1. Lie to the bank and not tell them about the UK property. You've now already declared it to one bank. Not sure if this means all banks will know about it.
2. Sell the UK property, and get a joint mortgage with our husband without any cuggle muggle. Rest easy on telling the truth, and have no worries about dealing with property in another country.
The question is would option 1 work out. UK property value is equal to the mortgage, rent is covering the mortgage. All good. Apparently property is rising in the UK, but it can just as easily go down. But and it's a bit BUT, you are paying interest only, so I think you are lucky to be able to sell in the UK without any cost to yourself. I'm not counting your 'lost' deposit. And you shouldn't focus on that. I imagine the Irish mortgage you are proposing will take all your income, so if anything at all were to go wrong with the UK property, damage, bad tenants how would you cover it.
My advise would probably be different if you didn't have an interest only mortgage.
One question, with what did or do you intend to pay back the capital on the UK property? Rising property prices?