A lot of Somali men are also unmarried, in their late thirties even. I bet if we carried out a study, we'd find comparable figures of single men and women. The trouble is that we are in the diaspora and the pool of eligible men and women is smaller and there is a lack of a network that can match people.
A lot of factors are involved in why people are married or unmarried, divorced or widowed.
We should refrain from conflating this with poor character and sinful lifestyles. Some people are tested with not getting married, some with losing their spouse, some with divorce.
Somalis place too much importance on 'marriage' and not enough on "do you worship Allah" and "what positive impact did you add to your society"?