Also, let’s not forget when Bob is catching Bomb Voyage and trying to keep Buddy from yeeting himself towards almost certain death, he’s on his way to his own wedding.
That makes two things abundantly clear:
Bob doesn’t have an aversion to working with other people. Remember when he runs into Elastigirl earlier in the day? She reminds him not to “forget”, and he promises he won’t. They were standing over a thief they ended up accidentally nabbing together, or so we thought. They bantered back and forth about working alone, yet they nabbed that thief so seamlessly, you’d think they’d done it before. Then you find out later, Elastigirl is the woman at the altar. Making it clear that they had to have worked together, very frequently, enough to end up trusting each other to the point that they revealed their secret identities and had a romantic relationship outside of Super work, culminating in literally marrying each other. Bob is more than fine with a partner because he married his.
The other is that, Bob is trying to protect Helen. She may be more than capable of handling herself, as she flirtatiously reminds Bob on the rooftop just hours before their nuptials. But the one thing that’s priceless to the Supers are their secret identities. With Syndrome following Bob begging to partner with him, it puts Helen in danger. A fanatical fan like that can end up possessive, meaning once Syndrome discovers her, could see her as a direct threat stealing “his” position working with Bob. And because he obviously has a knack for following people undetected (he was right on Bob’s heels all over a huge metropolitan city for literal hours), he could very well stalk Helen, discover her secret identity and expose her in order to eliminate her, putting her directly in danger. Bob isn’t an idiot, he knows working with this kid doesn’t just put this child in danger, but also his own wife and their identities. It’s better to say he works alone and let this kid down as gently as possible, hoping to finally shake him off for good so he can work in safety and peace.
Which leads me to my next point. Blaming Bob for all his friends getting killed is buying directly into Syndrome’s revisionist history of Bob “rejecting” him. Remember, if Syndrome hadn’t shown up to Mr. Incredible busting Bomb Voyage, none of the ensuing chaos with the bomb on the rocket boots getting dropped on the train tracks and blowing them up, causing Bob to lose Bomb Voyage, then forced to stop a speeding train, resulting in the passengers getting injured, the attempted suicide being thwarted which injured the guy, and everybody suing Bob for it, ultimately culminating in the Super’s fall from public grace and forced retirement. All of those consequences are because Syndrome refused to listen to Bob and meddled in dangerous affairs, making everything indescribably worse. If he had never showed up, none of the above would have happened and Supers would have never been forced into retirement, meaning none of Bob’s friends would have been lured from said retirement by Mirage and Syndrome’s private contract offers which resulted in their deaths.
