I'm not sure, if I'd call that 'multiple personalities', it sounds like an attempt at a 'rounded personality'. This is okay, but this can be confusing to readers if it's too rounded, because it could be hard pinpoint what their personality is. If they are too rounded, one could take that the character is lacking flaws.

The best thing I'd suggest is try to keep it believable. Even in the OP canon characters will have weaknesses or with will have limits of what they can personally take.

I hope that can help, if you have anymore questions I'll answer them ASAP. I got to head to work.