Maybe a person or letting go of a pet or possibly you quit a great job or gave up a hobby?
When the conflict of interest becomes too great.
Most decisions come down to short term enjoyment versus long term benefits, there will always be regrets no matter which way you choose.
Can I justify playing a couple of rounds of golf every week while I'm trying to save money to send two kids to college? $50 extra every week in the bank over 4 or 5 years can really add up, but golf was also the time I got together with my buddies every week. It's sad that I've lost touch with those friends since then but my kids got through college and are thriving.
When the bad outweighs the good.
In the last couple of years I've stopped drinking booze and it became more and more clear that I had a really unhealthy relationship with it, even when the good times were good the bad were really terrible.
Unfortunately I've had to let a very close but very toxic friendship go too after over ten years of being friends.
They're two of the best decisions I have ever made in my life.
Toxic friends are the hardest to give up, especially if you're anything like me and long term friends are hard to come by for whatever reason.
I think you can only make excuses for someone for so long, the ex-friend in question has a lot of issues and I have tried to help over the years and let things go because of it but I just got to a point where I had to cut ties. It's been really sad in many ways but I am so much better off now.