How fortunate you decided to verify the info you had! jabez married a MRS. Hannah Perkins!
Mr. Jabez Fitch Jun. and Mrs. Hannah Perkins, both of Norwich, were married June 3, 1760.
Cordilla Fitch, son, was born April 6, 1762.
Derius Fitch was born Jan. 2, 1764.
This is a different man.
Jabez Fitch, son of Jabez Fitch Jun and his wife Lydia, was born May 23, 1729. See. [http://dunhamwilcox.net/ct/norwich4.htm]
These may be related
Jabez Pirkins (Perkins?) and Hanah Lothrup were married June 30, 1698.
Jabez Perkins the son of Jabez and Hanah was born June 3, 1699.
Hanah Perkins was born Oct., 1703.
Mary Perkins was born Jan. 3, 1705/6.
Jacob Perkins was born May 22, 1709.
Luce Perkins was born July 12, 1713.
Judith Perkins was born March 2, 1715/4.
Hannah ye wife of Jabez Perkins dyed April 14, 1721.
Capt Jabez Perkins & Charity Lenard of Midlebury were married Dec. 17, 1722.
This book found in Google Books has a fair amount of the family history in Norwich and where they had come from.
Old Houses of the Antient Town of Norwich [Conn.] 1660-1800 Mary Elizabeth Perkins - 1895
Jabez Fitch (1737-1812) of Norwich, Connecticut and Hyde Park, Vermont, served as a soldier in the French and Indian War and the Revolutionary War. The Jabez Fitch diary, from 22 Aug. 1776 to 15 Dec. 1777, reflects his service as a lieutenant in the American army, and his experiences as a British prisoner during the Revolutionary War. Fitch was taken prisoner by the British at the Battle of Long Island, 27 Aug. 1776, and exchanged 15 Dec. 1777, after fifteen months and fifteen days in captivity, most of which time he was quartered at New Lots, Kings County, Long Island.
Good luck in your search!