This is a tough situtation as a member of a league and as a commissioner. I have been the commish for a fantasy football league for 5 years now and have been lucky not to have personally dealt with a situation like this.
What has occurred in your league could possibly be considered collusion. If two teams in the league make a trade because one guy/girl doesn't care anymore, then the trade shouldn't happen. Just because someone has written off their chances of making the playoffs doesn't give them the green light to have a fire sale. As a commissioner, if I saw this happening, the trade would be vetoed.
You have to be careful though. Sometimes a trade may happen where it seems lopsided because of the players involved when in fact it's a good trade for each team. If the the players involved help each team respectively then it must be allowed. Also, some guys don't quite have the same grasp on value for different players, positions, etc. In this case if a league member makes a trade because he doesn't know any better it must be allowed as well.
As for you and the guy proposing a trade to help you compete with "Crap Talker", don't do it, it's considered collusion. If you are the commish for this league, watch out for further deals like the one that took place and make a judgement call on whether the ones who have mailed it in are just giving their players away. If you are not the commish then send a message to the commish and let him know that the deal that took place is shady and to watch out for future deals like it. Remember, if guys are making deals that help out both sides, no matter how lopsided they may appear, they must be allowed.
Hope this helps. If you liked my response and have any further questions feel free to e-mail me at mailto:firstname.lastname@example.org
. Good luck!