Frustrating family members-self destruct types...how do you deal with them?

[TeddyTonksGirlfriend]

I have a very small set of close family members. Lots of drama in the wider family over the years mean I am this person's only support network. We had the same upbringing, same opportunities but have very different attitudes to life in general. I love family member to death but increasingly frustrated with what seems to be at least partially self inflicted problems, ranging from, but not limited to

-Almost deliberate financial mismanagement, struggling a bit slightly so will say fuck it and splash out on luxury items, trips and takeaways which are outside of what we'd consider reasonable to spend on, having a household income 4x theirs- obviously everyone has different attitudes to money and chooses to spend on different things but the level of spending is so divorced from the level of income it's dangerous
-Wilfully ignoring health issues, taking action that makes issues worse- not taking prescribed medication, not eating, then over eating. DC of family member is also becoming increasingly overweight and experiencing health issues related to this
-Seems unable to maintain healthy relationships- mixture of choosing (sometimes marrying!) partners who treat them like shit, but also falling out with friends, colleagues, bosses etc over what seems like minor issues

We have always gotten on well, enjoyed spending time together but myself and DH are increasingly called upon to come to the rescue when things go wrong: financially, emotionally and logistically... Has always been the case but far more so now and seemingly increasing all the time- very concerned about their mental well being and also completely exasperated by the impact it has on mine and my family's life, which I feel terrible for even saying but we also have a lot going on and can't sustain the level of support that is currently required.

Not sure why I am writing this really, maybe a bit of a vent, but if anyone has any advice that would be much appreciated, especially if you have been in a similar position from the outside looking in and watching someone repeatedly self destruct

[ChicCroissant]

Be less available for the disaster-drama bits, and more available when things run smoothly. Otherwise they will continue with the deliberate dramas if that is what gets them attention.

I assume it's a sibling?

[TeddyTonksGirlfriend]

I find it really difficult to be less available for the disaster drama bits as feel very guilty about leaving them to cope on their own 🙈

I do think you're right though, it's something I need to try to do.