One of the Catholic caricatures is the person overwrought with "Catholic guilt". Usually that guilt is the product of some sexual issue. Just to prove the point, I Googled the term "you'll go blind", then hit image search and, yep, within 3 images this came up:
There is an article on AOL.com (yes, I still look at AOL. I like the Black Crowes too. Leave me to my 90's reverie!). The article is concerned with a phenomena of 10% of women experiencing depression after sex.
The article says, "Some adults have mixed feelings about sex — from their upbringing, religion, or other influences — and may experience guilt or frustration after a sexual encounter. This may especially be a factor in people prone to sex-addictive behavior...."
The article deals with the issue (if indeed it is an issue) as if it were merely something to be treated with medicine or a therapist. Since it doesn't mention another dimension of sex, I will. I am speaking of the spiritual dimension.
We believe in conscience as Christians. Most of all, we believe in conscience formation. The Catechism tells us that ""Deep within his conscience man discovers a law which he has not laid upon himself but which he must obey. Its voice, ever calling him to love and to do what is good and to avoid evil, sounds in his heart at the right moment. . . . For man has in his heart a law inscribed by God. . . . His conscience is man's most secret core and his sanctuary. There he is alone with God whose voice echoes in his depths" (1776).
So, we have a conscience that is given to us by God. It's the natural tool that points us toward what is right and wrong. Is sex "wrong"? No. Not at all. But sex is sacred. It is sacred because it brings forth human life. Lives with souls. We promote chastity before marriage. The catechism says, "Chastity means the successful integration of sexuality within the person... Sexuality, in which man's belonging to the bodily and biological world is expressed, becomes personal and truly human when it is integrated into the relationship of one person to another, in the complete and lifelong mutual gift of a man and a woman. The virtue of chastity therefore involves the integrity of the person and the integrality of the gift" (2337).
In other words, there is a power of individuation in maintaining sexual abstinence to give oneself sexually is to give oneself totally to another.
From a spiritual perspective, the reason we feel guilty about things is most likely because we are guilty of things.
Lent is a time to get things right. If you are guilty, of anything, then spend some time in prayer, cleanse your conscience and make a confession.
The article concludes: "...experts agree it’s important not to dismiss your feelings, and to address any something’s-not-right emotions with your partner. If you often feel sad after sex and can’t pinpoint why, [talk]to your doctor and getting support from a counselor or sex therapist"
Or better, get absolution from your priest!