The Temple of Mara is in Riften, on the main strip close to the Jarl's home.
Some Draugr carry them usually. Otherwise, at the temple in Riften, the priest there has one for sale.
You can, but you need to: 1. Talk to the priest in the Temple of Mara, Riften before you can marry anyone. 2. Earn her favor by doing at least one of her miscellaneous quests. 3. Be wearing an Amulet of Mara (available from a quest chain from the temple of mara, or in a few dungeons) when you decide to "pop the question"
You must be in the Temple of Mara, wearing the Amulet of Mara, and if all those are met, then it is probably the companion glitch. If you have a companion with you, tell them to go away.
The Khajiit do not have a temple in Skyrim, or anywhere else in Tamriel.
You can buy one from the priest in the temple in Riften. Other than that, you can find them in dungeons or chests on your journeys. Some draugr will carry them as well.
Every town has a temple, the altar will be there, and all altars will cure disease. For example, the altar for the temple of Mara in Riften is to the right of the door as you enter.
You need an amulet of Mara, and they have to show interest in you when they see you wear it. If you do a quest for them, they are more likely to like you. If they ask you out, and you accept, you can plan your wedding at the temple in Riften
Go to Riften at the temple of Mara. Speak to one of the priests there about marriage- he will ask you if you want to buy an Amulet of Mara. Purchase and wear it while talking to her, do some errands for her, too, and eventually you might be able to marry her.
Usually, to get married in Skyrim, you will need to do a quest for the person you are trying to marry.
Speak to the priest in the Temple of Mara in Riften. He will explain that courtship in Skyrim is short, and that people wear an Amulet of Mara to show they are available and looking for a relationship. He will sell you one (note that you may have found one already, but the marraige options only become available when you speak to this priest). Wearing the amulet and talking to people will show that some are interested, possibly many people you already know, such as many of the Companions. Some characters require you to do something first, and this can differ depending on characters. Some require you to do a mission, some want a gift, etc.
Yes she does. Aphrodite is mainly the Goddess affiliated with love and beauty. Also, Mara is the Goddess of love in Skyrim.
Maramal can be found in the Bee and the Barb Inn inside Riften. He sells the amulet of Mara which allows you to marry.