I love Caron Simply Soft and have used it for all kinds of things (both knit and crocheted)--mainly because it's soft and machine washable, which makes it great for baby things.
I've never a problem with the yarn splitting or with picking up parts of other stitches. Are you using the correct size hook? You could try going up a hook size or two to see if that helps (it often does).
Sorry you're having such a difficult time!