Everyone has a bad day.
The number one thing to always remember when you're getting killed and the rage builds up is :

You brought people into the same situation.
Probably in that same round, you made people feel the same by killng them.
Its a normal process in a competitive FPS shooter and you should realize that a big part from winning is also losing or dying in a round, calculated or not.

Take it easy, remember all the guys you killed before, and make sure if you die, that it wasnt all for the cow by putting all your utilities out there when you engage a situation which might result in death, and in case of that, info your teammates instead of going full ♥♥♥♥♥♥ in the voice chat and afterwards infoeing, cause these 2 - 3 seconds can decide if your teammates survive, and eventually if your team gets the round.

When meeting toxic teammates, be kind and dont get on their level.
if you get mad and let yourself be provoked, it wont help you at all.

Some people just want to let out their rant, and you shouldnt feed them.
If they refuse to act normal just mute them and if necessary, report.

But remember at all times :

Keeping up the team spirit is the most important thing on Matchmaking !
When the teams raging and everybodys insulting each other, its already lost.

Wrote this while having a trust factor as low as the Earthcore because i argued too much with toxic people :)