Luke, I'm very sorry to hear it's all gone pear-shaped. Is it because aviation makes us bad people? NO, but we are, as a group, fairly self-centered, goal-oriented and a bit blinkered. We don't see the chaos we cause in the lives of those around us until it's too late, and they'll never appreciate the single-mindedness needed to qualify for, get, and maintain this lifestyle because we can't share it with them, unlike almost any other desirable job.
It's a fact of aviation life, I'm afraid, and it's not often because of straying eyes that relationships fold for aviators - although we're as susceptible to that as any other group in society. It's not right to say that 'if she loved you enough, she'd support you', because this career path is uniquely demanding on partners. Relationships that would survive elsewhere can't take the extreme stresses that this job puts on them.
Believe me, I know. I've lost two wives and my children because of my chosen career.