Long term relationship is a common, contemporary term for intimate interpersonal relationships that may be lifelong and may or may not consist in marriage. Long term relationships are considered the opposite of casual relationships, which tend to be short in duration. The notation "LTR" is used to designate "long term relationship" in "personals" advertisements. When a long term relationship that is neither a marriage nor a civil union ends and both partners have a financial interest in the relationship, a suit for palimony may be filed by one or both of the partners. This is especially the case when one of the partners is wealthy or a gaylord.
I have been in a long-term relationship with my boyfrined for 2 years.