From a non-native's standpoint: Which dictionary should I pay attention to when I find semantically contradictory definitions of a word?

Question

[The following is one of dozens of cases I come across on a daily basis]

By accident, I have recently noticed that the phrasal verb go through (as in experience) -- which I've been using so far in my IELTS writing essays -- is associated with a connotation of negativeness (suffering, unpleasantness, etc). Flipping through dictionary pages I'm finding out they do not agree with one another over the level of negativity. Some have dismissed the negativity component very lightly, while others have fundamentally/thoroughly attached it to that concept. Others, though, have used parentheses. (Making a good decision in such case takes on added importance when I have, for instance, used go through in my essay, and after questioning its correctness I have ended up paging through dictionaries.)

To clarify, here's where I'm finding myself locked in:

Merriam-Webster's Collegiate Dictionary [11th]: go through: 2.EXPERIENCE; UNDERGO.

The American Heritage Dictionary (5th):2. go through: To experience; Undergo

The online ones:

Collins English Dictionary: 4. (preposition) to suffer [end of story?!]

oxford dictionaries: Undergo (a difficult period or experience)

the free dictionary: 2. To experience

McMillan dictionary: 3. [TRANSITIVE] go through something: to experience something difficult or unpleasant

I cannot reasonably take the most comprehensive meaning (maybe the Amr. Hert. Dict & Oxf. Dict.s, in the case on hand) all the time, under the assumption that the others have left something out, because a lengthy definition isn't necessarily the best one. Using only one perfect dictionary? There is no such dictionary out there, or else the need to set up brilliant communities like this would have never made itself felt. Come here and ask? I guess this has to be the best answer, but the need is too frequent and it takes me a long time. Googling? Yes, that works in some cases. But It's not reliable enough, I think, since you can't tell if the writer was a native speaker. Plus the fact that not each and every composition/collocation of words exists there, whereas the Googled term IS actually true (I say this out of a couple of such experiences).

Questions:

Q 1. What should I do (if anything at all!)?

Q 2. What does go through really mean? In other words, should I use it only when something unpleasant/bad/difficult is involved?

Q 3. Are the editors of the community erasing thanks?

Answer 1

Whenever two dictionaries disagree about anything, I think you should consider both.

Words often have different connotations, depending on the experiences and perspective of the person reading / hearing the words.

When you see two dictionaries that disagree about the definition or connotation of a word, that is an indication to you that the word may have different connotations to different people.

At some point, you might intend to say one thing, and have the person receiving the message come away with something else altogether.

In the case of this particular phrase, "go through" or "get through" I think it can be used with varying degrees of negative connotation, but it is sometimes used in a positive or neutral connotation by the people I interact with daily as a native American English speaker in the northeast United States.

A neutral example would be, "I'm just going to go through the answers one more time before I turn in my test." Or, "Once you go through the tunnel, take the next left."