Widowmaker is in a good place now. I don't throw a fit if she's picked in my matches. When it comes to player performance, whether or not a hero is viable, and whether or not your team is bad and you belong with better players, there are some things to keep in mind.
First, if it's quickplay you have to completely forget things like "meta" "strategy" or trusting/relying on your teammates. You cannot make any general assumptions based on quickplay in Overwatch. Quickplay has a rating system like competitive which is hidden BUT it is entirely meaningless. Someone might have reached a high rating playing winston, but in your current match he's practicing genji and is terrible at it. This causes huge gaps when it comes to player performance in quickplay on top of a lot of players just not taking it seriously enough to really try to win. This means how well or poorly you or anyone on your/their team did means nothing here.
Competitive on the other hand does a good job of placing you at the proper skill rating after enough matches. If you get a widow on your team, check their profile and if they've played a lot of competitive widow, let them be. They obviously got to your level with widow and earned the right to play her without being harassed, the same goes for any other hero. Give them a chance until their pick is shown to clearly not work.
After a lot of matches you also have to accept that you are where you belong and you need to stop blaming others and instead analyze your own performance and cut down on mistakes. Something important to keep in mind below Diamond tier is that what makes a player good enough to have reached your skill rating can vary. Someone might have extremely good mechanical skills and manages to get lots of quick headshots, but if they're not at a high rating they probably have issues when it comes to other stuff, like general game sense and tactics and may be doing some pretty stupid things. Another person might have gotten there by playing very smart but lacks the accuracy to get consistent results from their good plays. If your teams seem to always be playing stupid or can't kill anything, realize that you are probably equally flawed in some ways combined to have been matched with them. The higher up the ladder you go though, the less weaknesses people have and you start seeing more consistency in your teammates and enemies because they have to both play skillfully and intelligently to be at their rating. Don't blame others, it doesn't help you improve at all. Acknowledge your weaknesses, and work on them and you'll climb. In the long run other players will be inconsequential.