Primary outcomes (emotion regulation, emotional distress, fatigue) and secondary outcomes (sleep difficulties, fear of recurrence, attentional bias, conjugal communication) will be investigated at 3 measurement times: before the intervention (T1), 3 months later (T2 - right after the intervention of the experimental group, and right before the intervention of the control group) and again 3 months later (T3 - after the intervention of the control group). Some questionnaires, two relaxation tasks, an attentional task, an actigraph and a smartphone application will be used to collect data. The indirect impact of the intervention on participants' partners will also be measured by questionnaires (emotional distress, conjugal communication).