Hi,
I am not researching your Caddens but I have had a quick look. There is a Michael Cadden married to a Catherine in the 1901 census. Also in the household is an Anne Cadden, described as a sister-in-law to Michael which would imply that Catherine's maiden name was Cadden. However in the 1911 census Anne is described as a sister to Michael implying that Catherine may not have been a Cadden.
I have found a marriage of a Michael CADDIN to a Catherine Somerville on 18 Nov 1885 in Irvinestown Church of Ireland. This may be totally incorrect but may be worth bearing in mind.
Regards