A lot of irritation has been expressed in Bible studies about the phrase "I am a jealous God." I think a little knowledge of the word in earlier English will help. It is related to Greek zelos and Latin zelus, with the pronunciation of the initial consonant changing in Old French on its way to English. Yes, now you see, I'm sure. It is the same word as "zealous." We can blame the French a bit, I suppose, because the positive word for desire and affection did acquire a negative sense there. Not the full-on pouting resentment we associate with the word "jealous" today, but the beginnings of that.
Why, then, do translators still use the word jealous, if the meaning is merely "greatly desire?" Wouldn't zealous be a better choice, then? I cannot answer for them, but the original sense in Genesis, from which Deuteronomy and the other books take their cue, includes a strong sense of exclusivity. All translations limp, and concessions have to be made. They have consistently gone in that direction.
It is interesting that in many Western languages the words for zeal and intensity acquire a negative sense, especially if they become associated with romance. In human interactions it does seem rather inevitable that an intense pursuit of a love object would quickly carry our modern resentful jealousy with it.
So keep "jealous" first in your mind when reading, but bring in "zealous" close after, to help wash away the negative taste. God desires you greatly.