Apparently, even without Galaxy, you can hover over portrait of people who sent you the invite and accept/refuse it to get rid of the notifications.

And how do I know the name of guy who sent me the invite?
Or I'm supposed to hover over all avatars until I find it? ;)

There, I sent you an invite so you can be happy.

Apparently, even if you do find him and ressolve the invite, the notification won't go away until you use galaxy anyway.

You've been inadequately informed apparently. :) At no point in time was Galaxy ever just a multiplayer gaming service back end. Right from the initial announcement from GOG it was presented quite clearly as being:

#1 - an optional DRM-free gaming client
#2 - a back end multiplayer matchmaking service able to play games cross-distribution-platform in games that support it (crossplay)
#3 - other optional backend services including achievments, social networking and other modern client+backend services and features

The initial announcement video that covers some of this:
https://www.youtube.com/watch?v=nyYW9AOWh-8&hd=1

Further announcements, videos since then expanded upon the details somewhat.

If a particular person has never actually watched GOG's initial announcement video and/or any of their followup videos, public interviews or public comments in the forums etc. I can understand how they might end up completely misunderstanding the goals/purpose/mission that GOG has with GOG Galaxy though because then it entirely falls within the realm of assumptions and rampant speculation ultimately.

If someone is more comfortable speculating blindly that's of course their choice, but I think there is a lot of value in watching and listening to what GOG actually has to say about what they're trying to do before anyone judges or criticizes them for it. Knowledge is power. Assumption and ignoring information just leads most likely to inaccurate judgment at best and from what I've seen a lot of fear, uncertainty and doubt purely based on uninformed rampant speculation in many cases at least. I'm not suggesting that everyone opposed to Galaxy is not informed, but it seems many are both uninformed and have no interest in trying to become informed or attempting to investigate in an unbiased manner.

In the end it is ultimately throwing the baby out with the bathwater.

You can't find out without galaxy or hovering about every avatar. That is the "fun" about this whole thing ;-)

lol, indeed, but there's only one option and that is "Accept Invitation". Shouldn't be the other one, "Deny Invitation", available too?

Only in Galaxy so far...

YOU'RE DOOMED TO BE MY FRIEND! COMPLY!

Nah, since here on the forums we are all friends so why should you want to decline? :P
This is really a mess without the client.

maybe this is one of the future galaxy "achievement" ... "find whomever sent you friend invites" :)

That's a good one. "Friends Forever!"

Seeing how the current rep system is mostly encouraging negativity, I guess there'll be an "enemy list" as well. ;)

Somehow related:
http://hatebook.org/

I'm actually thinking of trying it. I got a key last week and didn't care, now I dag it up for some impatient newbie who already got offline will likely not return until he gets the beta invite email. I'd offer it here, but the regulars should have it already (as it was sent to AvP owners, and AvP was free so every regular has it). I certainly don't want to open a new galaxy thread to offer my key, and I would get swarmed by noob PMs so I'll pass on that. Might as well redeem it myself.

It sure does not hurt to have a look. It is not like you'll be damned to use it if you don't like it :-)