If you are writing with precision in mind then, "I tend to over use (sic) semicolons because they help convey my fractured way of thinking." will suffice.

If you are writing dialogue, then what you wrote is fine. (You can write pretty much whatever you like in dialogue.)

The point is that writing is generally use to express something to the reader, so use whatever tools you have to accomplish that goal.

What’s fractured about “I use X because it helps me do Y” though? The semicolon didn’t convey that efficiently to me, but it did make the overuse point :)