How do you say "hard to overlook"?

Question

'Overlook' in the sense of forgiving, or letting something slide. All the words I can find that seem to be very close in meaning--大目に見る、不問に付す、聞き捨てにする、罷り通る--don't seem to be used in conjunction with にくい (or づらい), which is something I really want to use to get across that it's hard but not impossible. The closest thing I can think of is 許しにくい, but it lacks the indirectness and slight scorn that comes with the other verbs.

Context: "His actions are getting increasingly hard to overlook."

Answer 1

You could nominalize a word meaning "overlook" and then say that that is "getting more and more difficult" to do that.

Maybe something like this:

彼の行動を大目に見るのは段々難しくなってきています

• 大目に見る may have the connotation that you are have some authority over 彼.

彼の行動を黙って認めることは段々難しくなってきています

• 黙って認める could imply that you have been purposefully not speaking out until now but it has been bothering you for some time.

彼の行動を無視するのが段々難しくなってきています

• 無視する may imply that you have been trying to ignore his behavior for a while.

Answer 2

I agree that "にくい" and "づらい" are somehow somewhat incompatible with the phrases you suggested. I think the suffix "-難い(がたい)" fares a lot better with them (大目に見難い, 不問に付し難い, 聞き捨てにし難い, 罷り通し難い).

Also there's an idiom that captures the whole "hard to overlook" sense, which is:"目に余る". Using this expression, we may say something like:

「最近の彼の行動は日増しに目に余るようになってきている。」 Or more tersely, 「彼の最近の行動は目に余る。」

Answer 3

If you wish to use the word that connotes the meaning of 難い for you to be difficult to look over, you can say：

「許し難【がた】い」、「度し難【がた】い」、「看過【かんか】できない」、 「由々【ゆゆ】しく（由々しいことと）考える」、「[容赦]{ようしゃ}しない」、「（決して）容認【ようにん】できない」 and 「笑い事では済まされない ― It's not a laughing matter」.

When you say 許し難い,　許し難【がた】い would sound better than 許し難 【にく】い to carry the tone of seriousness and harshness.