Ok, I'd like to break this down. Your advice is to "guard your heart," then "Fall in love," then "never give all of your heart away." Which part of this is your real message?
I just talked to a woman who didn't love the guy she married and had kids with, then divorced him because later on she realized how unhappy she was. 70% of divorces are initiated by women, so within that statistic there are at least the same amount of women marrying men they don't love.
I'm noticing a growing trend of men-shaming articles written by women who a) don't understand mens' perspective and b) don't attempt to make an equitable attribution to the rise in singlehood and decline in relationship longevity.
Men and women are drifting further apart each year and there's a lot more at play than love. That's my opinion.