The problem with absent mindedness is that is it dismissed as just part of one's personality. Being an absent minded professor is almost a badge of honor. "It isn't my fault that I have such a brilliant mind that it is exclusively focused on important matters". I missed work meetings (people would just call me), I forgot final exams in college, I'd walk out of my house leaving the door wide open. When I forgot things that were important to others, it caused them pain and burden. But I dismissed it as "not my fault" because "I have a bad memory" or "I am always thinking about more important things and most people just can't relate".
Having a bad memory is easily remedied using notes, day planner (look at it each morning), smart phone apps, habits, etc. Using these tools will declutter your mind and inherently make you less absent minded. I have a fantastic memory now. And when I find my old ways creeping up (usually because I am short on-time or moving too fast) I immediately remedy it with planning.
Ultimately being absent minded implies "I don't care". I don't care enough to write things down or plan, or who I burden. If you think of it that way then you are more likely to improve. And if you are enabling someone who is absent minded, please stop. Tell them it isn't a symptom of brilliance or a genetic quirk. Every one has a smartphone. So it is a problem of not caring, lack of empathy, and irresponsibility.
As for gifts and travel, these are the major reason people fail to save enough money. If you are going to help someone in need, set a limit before you start helping. I've seen people self-destruct their high-paying careers because they felt too guilty to set limits. But without the high-paying job they can finally say no, without guilt.
Finally, you should travel because it makes you happy. Every year people joke that the holidays with the family involves getting the flu and intense family fights. If you are having this problem, explain that next year you won't travel if anyone in the house has a cold or until you personally establish habits that reduce your susceptibility to colds. When a fight gets out of control with your remote family explain that you might not visit next year until we can learn to be more civil. Establish a boundaries but also lower them once you as you build trust and respect.
Hope this helped.