Is this a Leak?How to fix?

[slim]

Lately, both live and online, I've been losing extra bets to check raises or raises on the RIVER when I value bet WHEN IT IS HU. Typical example is when I have AA or TPTK and board is not too scary....no obvious straights or flushes i.e. say I have AA and board is KJ754 or something like that. So I bet the river and it gets raised or cr by lone opponent. I have been calling even though I think I lost bc I don't want my opponent to walk over me. I think most people will agree that when you've raised preflop and/or on the flop and you bet all the way and still get raised on the river, your opponent is very unlikely bluffing assuming he is a typical player.

So my question is this: is calling that raise a leak in my game? I know some replies will be along the lines of "depending on your read of the situation and the board , you should fold" but I think that no matter what the board is (if I have AA and the board is as inocuous as K9732 rainbow), you hardly ever have the best hand if u get raised.
The other "solution" is to not value bet the river. I am quite aggressive when it is HU so I tend to bet on the river most of the time even if a 3rd flush card hits.For example, if I have AA and board is KcQc7s6s4c, I will still bet the river, but if it was KcQc9s7sTc, then I wouldn't bet. I think it is the right thing to do, but I welcome any advice.