one way is writing off your bitcoins as not yours. that money is not yours to spend. just forget about it. the more you look at it, the more you will just want to sell it especially when you see the value of bitcoin.
This is too much.
The Bitcoin is yours, try to discipline yourselves that is how you overcome temptation of selling. But do you know you can something that is not yours as long as it is in your custody. It doesn't matter if you take it like your own or it belonging to someone else. Once the fear, anxiety kicks in, the hands wither and would sell if in your custody.