Übersetzung - Englisch-Latein - My constant love

It´s for my ex-fiance(a woman). She´s returning home, far away for personal reasons, so I need to put this on two rings. But later i´ll see which part goes in what ring. I hope you can help me.
Besides this was written on spanish but i figure out there would be more english - latin translators than espanish - latin.
Thank for the suggestion chronotribe. As you´ll see i changed the text.

I've made a translation as accurate as I could. "Mea fidelis" literally means "my faithful" or "faithful mine". We couldn't translate "my love" by "mea amor"; "mea lux" ("my light") is a fair equivalent. "I'm sorry" could be translated in two different manners: by "da mihi ueniam" (=give me [your] pardon/pardon me) or "maereo" (I am full of sorrow/sad). Since it doesn't seem you have something to reproach yourself with, I've choosed the second. So it goes : "Tibi gratiam habeo/ maestus" = "To you I have gratitude/ [being] sorry"...
"From: XXX To: XXX" cannot just be translated with prepositions, for in Latin, there are declensions and the form of names change according to their functions.
At a pinch :
"XXX ad XXX"
Hope it'll be fine.