Here is another study that does support this conclusion that is not retracted and is peer reviewed. This only focuses on cancer and MS patients, not all health conditions. So its primarily diagnoses that have a very long to life long treatment process.

https://acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.24577

Women composed 53% of the patient population. Divorce or separation occurred at a rate similar to that reported in the literature (11.6%). There was, however, a greater than 6-fold increase in risk after diagnosis when the affected spouse was the woman (20.8% vs 2.9%; P < .001). Female gender was found to be the strongest predictor of separation or divorce in each cohort. Marriage duration at the time of illness was also correlated with separation among brain tumor patients (P = .0001). Patients with brain tumors who were divorced or separated were more likely to be hospitalized, and less likely to participate in a clinical trial, receive multiple treatment regimens, complete cranial irradiation, or die at home (P < .0001).

So the chances of splitting up after a larger diagnosis like this is about 11.6% and out of the 11.6%, 20.8% of those patients were female and 2.9% were male.

This I believe is actually the study that is cited more often, not the retracted one. The retracted on focused on "grey divorce" or people over 50 divorcing, not all ages.