Is It Common For Men That Are Diagnosed Stage 2

Is it common for men that are diagnosed stage 2 Prostate Cancer to push away there partners. My friend of 4 years said that it was the hardest decision for him to make. (to end a relationship) Although, the relationship had started to deteriorate it still took the young lady for a loop. His reasoning was, he didn't want to complicate her life and burden her with his health issues. They are both in there 50. Can the diagnoses of prostate cancer breakup relationships.