This list is directed at men; women who think they might be called to religious life can adapt, though I don't know much about discernment for women's orders (or men's for that matter).

1) I find women attractive.

Response: Good. That means you're a man with typical male responses. There's a joke that runs around in seminarian/prospective seminarian circles about a young priest who asks a much older when when women stop looking attractive. The answer depends on who's telling the joke, but it's somewhere between 15 minutes and two days after you're dead.

That doesn't mean priests are miserable, BTW. Married men have to learn how to deal with women who might be more attractive than their wife (and seeing a wife as a substitute for someone else is a horrible way to treat her). Celibate men have to learn healthy ways of dealing with this attraction (and such ways do exist).

2) I find the thought of family and fatherhood attractive.

Response: Good. You should, because they are good things. That doesn't mean you aren't called to spiritual fatherhood.

3) I struggle with serious sins.

Response: This isn't a deal-breaker. Particularly in these days, we're subject to all sorts of pressures that lead us into sin. You will need to address those sins, but the mere fact that you are struggling with them instead of just giving in means that you're trying to move in the right direction. This is one reason that a good spiritual director can be a great help in discerning a vocation.

4) I couldn't be happy as a priest.

Response: There are some unhappy priests, no doubt about it. But a lot of the time, what we think will make us happy is what our materialist culture tells us will make us happy. What really makes us happy is being what God made us to be.

So this can be a real objection, but you need to start asking whether the fear of unhappiness stems from an unhealthy attachment to worldly things, or whether God really is calling you to be something else.

Great list Obi. A saint, whom I don't remember the name of said that 1/3 where called to the religious state (either secular or religious) and it is obvious that a great many of these turn down there true vocation.

Very nice list indeed

St. John Bosco. It's possible his estimate was high, but I'm confident the proportion is not nearly as low as the number of people who actually pursue a religious vocation.