It’s an interesting phrase. OED has entries for both positive and negative senses, ie mutual affection and no affection. (The earlier sense is marked as obsolete.)
love, n.1 P7
a. In a positive sense: ‘their (our, etc.) affection is mutual’. Obs.
1600 B. Jonson Every Man out of his Humor ii. i. sig. E.ii Car… Hee loues you well Signior. Sog. There shall be no loue lost Sir.
c1640 R. Davenport Surv. Sci. in Wks. (1890) 327 Oh my sweete! Sure there is no loue lost when you two meete.
1696 W. Bates Acct. Life P. Henry (1699) 8 Dr. Busby..took a particular Kindness to him,..and there was no Love lost betwixt them.
b. In a negative sense: ‘they (we, etc.) have no love for each other’.
?1622 J. Taylor Trav. Twelve-pence in Wks. (1630) i. 71 They loue me not, which makes ‘em quickly spend me. But there’s no great loue lost ‘twixt them and mee, We keepe asunder and so best agree.
1751 S. Richardson Clarissa (ed. 3) III. xxv. 134 He must needs say, there was no love lost between some of my family and him; but he had not deserved of them what they had of him.