Measures of mental well-being and social/emotional isolation were applied to a cohort of fathers seeking assistance from a Welsh charity. The fathers approached the charity predominantly with child arrangement problems after parental separation. Well-being was found to be strongly degraded – and loneliness severely increased – in this cohort compared to general populations. Associations of these dependent variables with nine predictor variables were explored, the latter being: a domestic abuse risk index, low income, allegations of abuse against the father, social services involvement with the family, refusal of the ex-partner to consider mediation, the father’s concern about abuse of a child by the ex-partner or her new partner, the father’s disability, the restriction of child contact, and an indicator of the father’s recognition of his need for emotional support. The fathers’ risk from domestic abuse was the variable most strongly associated with poorer well-being and elevated loneliness, as well as with a separate indication of depression/suicidality. The variable which was the second most strongly associated with those three dependent variables was low income, mostly due to unemployment. The findings of the study challenge the notion that serious partner abuse of men is either relatively uncommon compared with that of women, or that it is less impactful.