I think the key point of Night City is
No one gets a happy ending
You simply don't. Even if you're a legend, you're not a legend because you're sitting in the back of Afterlife enjoying a drink. You're the legend because you have a drink on the menu and buried somewhere.
Evelyn is an amazing character, she's a tragic character who had her back against the wall and was attempting to make big moves. The problem with this, and imo also a flaw with Judy, is they don't understand Night City. These power moves have cause and effect;
Stealing the Relic
- Betraying Arasaka
She was willing to get close to the temperamental son, who was known to be hot headed, and have a violence past. She was attempting to steal everything that he was attempting to steal just to make money.
Realistically; this was playing with a fire that was WORST than the other betrayals because unlike the others he has the power behind and instability to harm her.
- Betraying Dex
She asks V to cut Dex out of the payment, she even tries to make it sound that SHE has more power than Dex does even though that hasn't been proven. It also almost shown that she was wrong. She didn't hold any cards in her hand, she was instead being puppeteer by others.
This might have been the second safest since Dex as far as we know, isn't that powerful. At least not compare to the other people on this list. He's just now starting to rebuild his group, and make everything back to normal, so betraying him -might- have been safe up to some point. She could have easily left town, and most likely would have been fine.
- Betraying V
She -never- warns you the danger of placing the shard within Jackie's head, which was either knowingly or unknowingly the reaction that would follow afterwards. If she knew, she knew the risk that was being taken and never said a thing, if she unknownly knew about it, that means she didn't do research.
She wanted you to cut Dex out of the deal, Dex would have found out and when he did, he would have gone after V. He has the connections at the Afterlife and we already saw how the heist in a way ruined V's Rep with people. During the phone call with Rogue, she tells you that's why no one wants to work with V. Picture of Dex was alive?
This was the safest of the betrayals because you are nothing in the food chain. At most? You can go after her, but she has more connections and at the end of the day more connections = more power.
- Betraying The Voodoo Boys
The Voodoo boys were already planning on betraying her, while she was planning on betraying them. This was a deadly game and probably the dangerous on the list because while Araska is the stronger, it was establish how dangerous they can be with the net and what they all know about it.
Evelyn was not going to survive, no matter how you cut the cake. Her piece was being served it was just a matter of -how- and -who- would do it. That's tragic sad, but in a twisted way, this was probably the best option that she took her own life instead of living in fear and having to wait for the bullet that had her name on it. If this was real world? Yes, never the option but this is Night City where you find out that people have murdered each other over standing on the wrong corner.