Green’s Dictionary of Slang

I trust and love you, written on envelopes of love letters.

1945		D. Bolster Roll On My Twelve 135: I.T.A.L.Y. ... I Trust And Love You.
2002		‘Hectic James’ HecticJames.com ‘Stuff’ 30 Sept. 🌐 These are shorthand acronyms used by lovers, such as SWALK for Sealed with A loving Kiss. Other examples given were: [...] ITALY: I trust and love you; NORWICH: (K)nickers off ready when I come home.