I was in a similar boat myself (until quite recently). My portfolio was nearly all index funds, with the exception of a chunk of AAPL I bought years ago. After the recent massive run-up in share price, AAPL had become about 1/3 of my liquid net worth. As much as I respect Apple as a company, the stock looks to be overbought... and I have clear memories of past years when AAPL got beaten down even while other tech names did not. That said, I couldn't bring myself to just sell the shares. It's hard to sell winners!
At any rate - I landed on a strategy of selling out-of-the-money covered calls, figuring that the incentive of getting some cash up front in exchange for agreeing to give someone the opportunity to buy my AAPL if the price went up even more would be enough for me. So I sold some $460 Sep 21 calls when AAPL was around $445... and the stock ran up to around $460. So I figured hey, let's do some more, and sold covered Sep 21 calls on the rest of my AAPL at $480. Sure enough, the stock finished around $500 last week all the calls were exercised.
I spent some time this weekend feeling sorry for myself that I had sold the calls - after all, I would be about $20,000 richer if I hadn't done so. At the end of the day though I'm a value investor, selling AAPL was the right thing to do, and I sold the covered calls as part of a principled plan intended to give me a good exit on the AAPL shares one way or another. In fact, if I hadn't sold AAPL calls before I would do it now.