The wife is not much of a drinker but does enjoy the occasional after-dinner aperitif. Her favorites are Bailey’s and Kahlua (the latter especially poured over ice cream), but even then she can make a bottle last for months. She’s also tried and liked Galliano and limoncello.
What are some others you might recommend?
Gran Marnier (orange peel liqueur).
Malibu coconut/rum liqueur
Frangelico (hazelnut liqueur)
Absinthe
Peppermint schnapps
The Godiva chocolate liqueur is good.
1 part chocolate liqueur
1 part vodka or soju if you want the drink a little weaker
1/41 part vanilla extract
mix over ice strain into martini glass and enjoy.
St. Germaine Elderflower Liqueur – wonderful stuff. And a dollop to a glass of champagne, and works surpisingly well with gin.
Canton Ginger – delicious! brandy, ginger liqueur with just a touch of vanilla. Wonderful by itself, wonderful in drinks. Enough real ginger in it so that my mother uses it medicinally, to settle her stomach.
Jägermeister? 
Godiva makes some Godiva chocolate liqueurs.
It sounds like she has a sweet tooth when it comes to her after-dinner drinks, so I don’t know that I would recommend things like the fruit liqueurs I’m familiar with:
Kirsch (cherries) Kirsch - Wikipedia
Pear Poire Williams - Wikipedia
Most women like Amaretto.
Amaretto is pretty good
ETA: I am not a woman
I was introduced to La Extremeña acorn liqueur on a trip to Spain. It is quite delicious. Nutty, sweet and warm.
I bought a bottle of muroise on impulse a few years back, and thought it was fabulous. Too bad I’ve never seen it anywhere since!
Frangelico is yummy, too. And Kahlua certainly has its moments.
screaming orgasm
1part kahlua (bottom 3rd of a shot glass)
float 1 part baileys on top of that
float 1 part vodka on top of that.
you end up with a 3 layered shot, its an interesting experience drinking those
Brave Bull: 1 part Kahlua (or Tia Maria), 1 part tequila.
St. Germaine is my latest favorite liqueur. Very light, delicate, and yummy.
I’m also doing a fair bit of Lillet lately.
If she likes sweet cream-based liqueurs, she’d probably like Tres Leches.
For a long time my favorite liqueur was Bonny Doon Framboise. The intense raspberry flavor was like distilling everything wonderful about summer into a bottle. Then a few years ago they stopped making it.
I’ve tried making some with my homegrown raspberries and vodka, but it still needs improving.
This thread inspired me to look again, and I found that some former Bonny Doon winemakers are making their own Framboise now at Pacific Rim Winemakers. I will be tracking some down to try it.
Cream sherry; there is a nice one that comes in a blue glass bottle. I can’t remember the name now.
I also enjoy red vermouth. It is sweet with an aftertaste of grapefruit peel.
Chambord.
And Chambord over ice cream!