I think they are victims of unrealistic expectations, coupled with cultural pressure and expectations. It really seems to me that a lot of vocations, not necessarily abnormal sexually, are by default because they don't seem to fit any other mold. There are many heterosexuals in the priesthood who are emotionally immature; some are unbalanced; others seem quite normal and stable. I haven't come to the above thinking entirely on my own; others have noted immaturity on the part of the clergy.
The laity are part of the problem. They need the ideal and expect priests to be something they could never be themselves. They have put them on pedestals because they have to believe the fantasy that they are holier, merely because of their vocation, than others.
When you read about the apostles, they come across as fairly normal men, even though information about their private lives isn't given. I had trouble with St. Paul for awhile, but I do admire him that he worked and didn't expect a free ride from his parishioners. That probably wouldn't be practical today. In large parishes a priest couldn't really do his job with so many sacramental obligations, without burnout.
Sometimes I wonder if Augustine would have made a holier choice if he had married the mother of his child. I'm told they may have been unequals socially. His later philosophy, while not necessarily bad, may have been trying to rationalize his own conflict between his mother and the woman and the normal right thing to do. That may not be the case, but I'm weary of trying to see holiness where it may have been absent
I do think you're getting somewhere about the overnuancing of sexual morality in the Latin West. When every activity (no matter how mundane) is a grave sin, no activity is sinful. In ther words, be careful about how many rules you make - if you make too many, all will be ignored.
Many catholics seem to be able to comfortably ignore all the rules, which in some cases seem to be excessive and exaggerated. Same with our society where there are so many laws now, people don't even know they have broken one until they get caught. People start to think, "I'm going to sin (or break some law) anyway so why worry about it any more?"
As to your comment about convents in the east vs. convents in the west, I wouldn't know. The east culturally had a tendency to hide their women in the world. The early Christian singles in the NT seemed to fit in quite wholesomely with the others and were a part of normal Christian everyday life.
I think that is why we are losing vocations and I'm not convinced it is necesarily a bad thing. How is a nun holier (and she is treated as such in the church as a given) as a laywoman who does the same things, prayer, continence, charitable works, etc.). I do acknowledge that historically it wasn't safe or economically feasible for single women to remain in the world. Furthermore, marriage entailed so many different sorrows in those times, that many women would be tempted to escape them.
There is really no right or wrong about these customs per se but presenting a false picture to the young about various aspects of a narrow interpretation of holy living can cause a lot of unnecessary unhappiness and conflict. The bottom line is fully mature, informed, voluntary consent to such choices.
You seem to be biased towards the east; from my vantage point, both east and west seem to have perpetuated customs that are difficult to understand in our modern world. In some ways, it does seem that the east wasn't quite so stringent other than the Lenten fast. I can't imagine being able to keep up with that, but that is cultural, too . . . In many ways, it's the same in the world. People are held to narrow channels, career paths, etc. It's seems to be a human and societal tendency to control peoples lives more than is really warranted.
Think of it like this - Christianity spread pretty rapidly through the Roman Empire, but because of the persecution, there was not a general inclination to have large monastic communities. The red martyrs through this phase tended to be ordinary people - artisans, soldiers, servants, some civil servants - they were all part and parcel of their communities, and spread the word of Christ through inspirational acts and demeanor in daily life. They were inspiring, and they were normal. Once the persecution ended, monastics became the ideal - living outside the community, yet soaking up time and treasure, yet no one ever understood the aim.
If monasticism is the goal of a society, then then society destructs upon the reaching of that perfection, because that world is communist and without physical or emotional passion. Sterile.
So ultimately, Christianity may have been put in the hands of people who didn't understand their own direction, and who weren't responsible for the great mass of conversions which occurred over time.
You see a lot of it with Augustine, who struggled mightily with apparent bisexual tendencies (Confessions makes it pretty clear to me).
Once monasticism became something to admire in clerical culture and withdrawal from society became idealized, a clergy not firmly rooted in the world would lose its ties to the very society it served.
I noted that there was a minimum age for ordination in the 4th century - which was 30, in commemoration of Christ's age when he began a ministry. Considering that it would also ensure emotional and intellectual maturity, it was a good thing.
I'm going to have to review "The Desert Fathers" as well as "The Ascetical Homilies of St. Isaac the Syrian" to come up with some better answers. I know that I started skimming the first 7 Ecumenical Councils last night after a lengthy hiatus. It is illuminating.