The Tories rightward swing has made them un-electable in the eyes of most people in the U.K, and their voters are getting older every year (the average age of a Tory member is over 65... and it's almost that grim with their voters. Not as extreme a pattern as the CDU in Germany though...).
I don't know who told you the myth that the CDU is dying out (I suspect Lewis Trondheim
), but I can assure you it is not true.
It is true that the CDU gets their best results in the group of voters >60, but in most cases the differences among age groups are not very dramatic.
Moreover, in the last few elections the age structure of the SPD voters was quite similar to that of the CDU.
For the Greens it's almost the other way round. They do much better than average among younger voters (<30, 30-44), but are very weak among those over 60. (Though I guess, this will change with the Green core voters getting older...).
FDP does slightly better among younger voters in recent elections.
The following results are taken from exit polls by Forschungsgruppe Wahlen:
http://www.forschungsgruppe.de/Ergebnisse/Wahlanalysen/PARTY age groups: <30/ 30-44/ 45-59/ >59
General election 2002
CDU/CSU 33/34/39/45
SPD 37/39/37/38
Greens 11/11/9/5
FDP 10/9/7/6
State Election Lower Saxony 2003
CDU 48/47/47/50
SPD 29/34/34/34
Greens 9/10/7/6
FDP 8/6/9/9
State Election Bavaria 2003 (My favourite one
)
CSU 59/58/61/66
SPD 13/16/19/24
Greens 12/12/8/3
State Election Hamburg 2004
CDU 42/41/45/58(!)
SPD 27/29/32/30
Greens 20/20/14/3
EU Election 2004
CDU/CSU 39/38/41/54
SPD 19/20/24/25
Greens 17/19/13/4
FDP 9/7/7/5
State Election Thuringia 2004
CDU 42/41/45/48
SPD 12/12/14/20
PDS 22/26/29/26
State Election Brandenburg 2004
CDU 16/-/-/- Overall: 20
SPD 24/-/-/- Overall: 32
PDS 23/-/-/- Overall: 28
DVU 13/-/-/- Overall: 6
State Election Saxony 2004
CDU 39/41/43/47
SPD 8/8/8/8/15
PDS 16/21/25/26
NPD 17(!)/-/-/- Overall: 9.