Varieties of Interpersonal relationship ?

Interpersonal relationships include kinship and family relations in which people become associated by genetics or consanguinity. These include such roles as father, mother, son, or daughter. Relationships can also be established by marriage, such as husband, wife, father-in-law, mother-in-law, uncle by marriage, or aunt by marriage. They may be formal long-term relationships recognized by law and formalized through public ceremony, such as marriage or civil union. They may also be informal long-term relationships such as loving relationships or romantic relationships with or without living together. In these cases the "other person" is often called lover, boyfriend, or girlfriend, as distinct from just a male or female friend, or "significant other". If the partners live together, the relationship may resemble marriage, with the parties possibly even called husband and wife. Scottish common law can regard such couples as actual marriages after a period of time. Long-term relationships in other countries can become known as common-law marriages, although they may have no special status in law. The term mistress may refer in a somewhat old-fashioned way to a female lover of an already married or unmarried man. A mistress may have the status of an "official mistress" (in French maîtresse en titre); as exemplified by the career of Madame de Pompadour.
Friendships consist of mutual liking, trust, respect, and often even love and unconditional acceptance. They usually imply the discovery or establishment of similarities or common ground between the individuals.[2] Internet friendships and pen-pals may take place at a considerable physical distance. Brotherhood and sisterhood can refer to individuals united in a common cause or having a common interest, which may involve formal membership in a club, organization, association, society, lodge, fraternity, or sorority. This type of interpersonal relationship relates to the comradeship of fellow soldiers in peace or war. Partners or co-workers in a profession, business, or common workplace also have a long term interpersonal relationship.
Soulmates are individuals intimately drawn to one another through a favorable meeting of minds and who find mutual acceptance and understanding with one another. Soulmates may feel themselves bonded together for a lifetime and hence may become sexual partners, but not necessarily. Casual relationships are sexual relationships extending beyond one-night stands that exclusively consist of sexual behavior. One can label the participants as "friends with benefits" or as friends "hooking up" when limited to sexual intercourse, or regard them as sexual partners in a wider sense. Platonic love is an affectionate relationship into which the sexual element does not enter, especially in cases where one might easily assume otherwise.