According to Satyacharya, the lord of the Rasis (Signs) falling in the 2nd, 4th, 5th, 8th, 9th and 12th from the Mulatrikona of a Graha (Planet) are friendly to that Graha.
There are Groups of planets which go good with each other and then there are planets which shows clashes.
Arudha Lagna is a method to know the perceive image of a person (or his/her personality) in the society by utilising Astrology.
The failure of love relationships can be due, 1. Obstruction by parents. 2. Backing out of the partner. 3. OR backing out of native himself.