A table cell contains multiple values separated by commas e.g A,B,C,D,A,E,C then how to remove the duplicate values

DECLARE @tmp VARCHAR(30)

DECLARE @t TABLE (RowNo INT, MyValue VARCHAR(10), Remainder VARCHAR(30))


SET @tmp = 'A,B,C,D,A,E,C'

;WITH MyCTE AS
(
	SELECT 1 AS RowNo, LEFT(@tmp, CHARINDEX(',',@tmp)-1) AS MyValue,  RIGHT(@tmp, LEN(@tmp) - CHARINDEX(',',@tmp)) AS Remainder
	WHERE CHARINDEX(',',@tmp)>0
	UNION ALL
	SELECT RowNo +1 AS RowNo, LEFT(Remainder, CHARINDEX(',',Remainder)-1) AS MyValue,  RIGHT(Remainder, LEN(Remainder) - CHARINDEX(',',Remainder)) AS Remainder
	FROM MyCTE
	WHERE CHARINDEX(',',Remainder)>0
	UNION ALL
	SELECT RowNo +1 AS RowNo, Remainder AS MyValue,  NULL AS Remainder
	FROM MyCTE
	WHERE CHARINDEX(',',Remainder)=0
)
INSERT INTO @t (RowNo, MyValue, Remainder)
SELECT RowNo, MyValue, Remainder
FROM MyCte 

--display MyCTE data
SELECT *
FROM @t

--get duplicates
SELECT MyValue, COUNT(MyValue) AS CountOfMyValue
FROM @t
GROUP BY MyValue
HAVING COUNT(MyValue)>=1

DECLARE @srctbl TABLE (id INT IDENTITY(1,1), names VARCHAR(50))

INSERT INTO @srctbl VALUES ('abc,jkm,pqr,abc,def,ghi,jkm,ghi'),
('mno,pqr,abc,mno,pqr'), ('abc,jkm,stu,jkm,rcm,tin')

DECLARE @dsttbl TABLE (id INT, RowNo INT, MyValue VARCHAR(10), Remainder VARCHAR(30))
 

;WITH MyCTE AS
(
	SELECT id, 1 AS RowNo, LEFT(names, CHARINDEX(',',names)-1) AS MyValue,  RIGHT(names, LEN(names) - CHARINDEX(',',names)) AS Remainder
	FROM @srctbl 
	WHERE CHARINDEX(',',names)>0
	UNION ALL
	SELECT id, RowNo +1 AS RowNo, LEFT(Remainder, CHARINDEX(',',Remainder)-1) AS MyValue,  RIGHT(Remainder, LEN(Remainder) - CHARINDEX(',',Remainder)) AS Remainder
	FROM MyCTE
	WHERE CHARINDEX(',',Remainder)>0
	UNION ALL
	SELECT id, RowNo+1 AS RowNo, Remainder AS MyValue,  NULL AS Remainder
	FROM MyCTE
	WHERE CHARINDEX(',',Remainder)=0
)
INSERT INTO @dsttbl (id, RowNo, MyValue, Remainder)
SELECT id, RowNo, MyValue, Remainder
FROM MyCte 
 

UPDATE t3 SET  t3.names = t4.names
FROM @srctbl AS t3 INNER JOIN (
	SELECT  t1.id, STUFF( (SELECT ',' + MyValue AS 'text()' 
					  FROM (
	  					SELECT id, MyValue 
						FROM @dsttbl 
						GROUP BY id, MyValue
						HAVING COUNT(MyValue)>=1
					  ) AS t2
					  WHERE t2.id = t1.id
					  FOR XML PATH('')), 1, 1, '') AS [names]
	FROM @dsttbl  AS t1
	GROUP BY t1.id
) AS t4 ON t3.id = t4.id 

SELECT *
FROM @srctbl