in poetry and song lyrics, the authors often take liberties with the English language and use verb tenses that may not mean any sense grammatically. In your example :" Love just don't come easy" the correct English would be "Love just doesn't come easily" or "Love just does not come easy" but the singer felt this verse sounded or rhymed better with the other verses and wrote it that way. My advice, when it comes to songs and poetry, don't sweat the grammar, just sing along...

'love', pronunciation [luhv] is a noun or a verb as in to love , loved, loving. It is a singular noun. 'Loves' is the plural form. Meanings: 1. a profoundly tender, passionate affection for another person. 2. a feeling of warm personal attachment or deep affection, as for a parent, child, or friend. 3. sexual passion or desire. 4. a person toward whom love is felt; beloved person; sweetheart. 5. (used in direct address as a term of endearment, affection, or the like): Would you like to see a movie, love? 6. a love affair; an intensely amorous incident; amour. 7. sexual intercourse; copulation. 8. (initial capital letter) a personification of sexual affection, as Eros or Cupid. 9. affectionate concern for the well-being of others: the love of one's neighbor. 10. strong predilection, enthusiasm, or liking for anything: her love of books. 11. the object or thing so liked: The theater was her great love. 12. the benevolent affection of God for His creatures, or the reverent affection due from them to God. 13. Chiefly Tennis. a score of zero; nothing. 14. a word formerly used in communications to represent the letter L

Meanings of 'love' as a verb used with object) 15. to have love or affection for: All her pupils love her. 16. to have a profoundly tender, passionate affection for (another person). 17. to have a strong liking for; take great pleasure in: to love music. 18. to need or require; benefit greatly from: Plants love sunlight. 19. to embrace and kiss (someone), as a lover. 20. to have sexual intercourse with. –verb (used without object) 21. to have love or affection for another person; be in love. —Verb phrase 22. love up, to hug and cuddle: She loves him up every chance she gets. —Idioms 23. for love, a. out of affection or liking; for pleasure. b. without compensation; gratuitously: He took care of the poor for love. 24. for the love of, in consideration of; for the sake of: For the love of mercy, stop that noise. 25. in love, infused with or feeling deep affection or passion: a youth always in love. 26. in love with, feeling deep affection or passion for (a person, idea, occupation, etc.); enamored of: in love with the girl next door; in love with one's work. 27. make love, a. to embrace and kiss as lovers. b. to engage in sexual activity. 28. no love lost, dislike; animosity: There was no love lost between the two brothers.