Flush over flush odds

I see it happening pretty much every day but I have no idea what are the odds here. Searching the Web has yielded a lot of different opinions and I am not sure which number is actually correct.

1) So, in a FR game if:
- the board on the flop contains 2 flush cards
- the board on the river contains 3 flush cards
- one player has 2 of the same suit in hand

... what are the odds the other guy (assume it is heads up) also has 2 suited cards in the same suit in the hand?

This is important since so many times I see people pay to draw to non-nut flush.

2) What are the odds in 6-max game instead of FR?

Its not that important, if we flop a flush we should be looking to get it in majority of the time.

If we're beat then so be it.

I have no idea what the odds are. It really depends on how loose people play their suited cards. I usually avoid trying to make a big pot with small suited cards when I have a flush and opponent is being aggressive. Most times, you should just try getting value - I dont think you can just outright fold when you do hit a flush.

there are not so many odds, just think about it if we say there are 3 suiters on the board you two also have two of them. That means there are given 7 cards out of 9 from one colour...
in total there are 13 within 52 cards, the chance is already small....but if you have 2 suited cards it is very unlikly that you have 23 or something... so even not all 2 suited cards will beat you
all in all a flush wit three of the colour on board is always a good pot to win

CO: $1.14
BTN: $2.00
Hero (SB): $2.05
BB: $3.22
UTG: $1.11
UTG+1: $2.49
UTG+2: $2.00
MP1: $1.40
MP2: $2.21

Pre Flop: ($0.03) Hero is SB with 8 K
UTG calls $0.02, 4 folds, CO calls $0.02, 1 fold, Hero calls $0.01, BB checks

Flop: ($0.08) 2 5 T (4 players)
Hero bets $0.04, BB folds, UTG calls $0.04, CO raises to $0.08, Hero raises to $0.12, UTG calls $0.08, CO raises to $0.16, Hero raises to $2.03 all in, UTG calls $0.97 all in, CO calls $0.96 all in

Turn: ($3.41) J (3 players - 3 are all in)

River: ($3.41) 5 (3 players - 3 are all in)

Final Pot: $3.41
CO shows Q 9 (a flush, Queen high)
Hero shows 8 K (a flush, King high)
UTG shows Q A (a flush, Ace high)
Hero wins $0.06
UTG wins $3.13
(Rake: $0.22)

This kind of crap happens with astonishing regularity Seriously, what the ****?

P.S. I figured CO has the Ace, probably not paired with the 2nd flush card. Stupid me. BTW I am 78% favorite when money goes in, which is practically the same as 0%. I am losing with non-nut flushes around 70-80% of the time (usually to the nut flush since everybody keeps Ax suited).