The Heart Meter

Black
They are indifferent, you are just a stranger to them.

Purple
They want to get to know you better, you seem like a nice guy.

Blue
They consider you one of their friends, they can talk to you easily.

Green
They consider you a good friend, but they are also flirting a little.

Yellow
They consider you their best friend, and are starting to flirt quite alot.

Orange
They consider you their boyfriend, they really care about you.

Red
They consider you husband material, they love you and want to marry you.

Courting/Marriage

Courting the girl of your choice is simple. Present her favorite gifts to her everyday, and talk to her until she repeats herself. Also make sure to invite her to all the special events in the village. Make sure to give her a gift on her birthday, and never forget it!

To marry the girl of your dreams, you will need three things.
1.) The final house extension
2.) The girl up to a red heart
3.) The blue feather *

* - The blue feather will be available at the supermarket when the girl only has an orange heart. You can buy the feather, but if you give it to her when she still has an orange heart, she will turn you down.
* - Won will stop by your house sometime and offer to sell you the blue feather, don't buy it from him! Just wait for the one at the supermarket, it's alot cheaper.

After you give the girl the feather, I'm pretty sure you have the marriage a week after. If you look on your calendar, the date will be marked with a heart.

Baby

After one season of marriage, as long as your are being really nice to your wife (i.e. gift everday), she will start to say she if sick or is feeling odd. After a few more days you can go to the clinic, and there she will announce she is pregnant. After another two seasons she will give birth to a baby. It will always be a boy, and you can't have more then one.

The Stages

Likes everything else in the game, the baby will have a heart meter.

Stage 1 : Only your wife will be able to hold the baby, you will have no interaction with it at all.
Stage 2 : The baby will be able to crawl. You can't pick it up, but you can talk to it and give it gifts.
Stage 3 : The baby will now be able to walk and talk gibberish. You still can't pick it up, but make sure to give it gifts!

Divorce

Divorce is pretty basic. Just give your wife the thing she hates most, and her heart level will slowly start to drop. Eventually she will leave you and go back to her parent's house. Be warned though. With divorce comes consequences. Your percentage will drop, and you will most likely loose friendship with her family, because they will be very angry with you. The other villagers will be a little upset too, and that could put your frienships at risk. I'm pretty sure you aren't able to marry another girl during the breakup.