Non-romantic relationship question - when someone you want to like/love drives you crazy?

[BelindaBanana]

I have recently read that you can't change a person - you can only change YOUR reactions to them.

But HOW do you do this?

One person X is a kind of colleague who I see regularly (can't avoid really)
I do want to like this person but I do get that it's no big deal if I can't make my reactions to X change but their behaviour is very superior when my head tells me that there's a lot of insecurity there. X makes my blood boil sometimes but I also pity x because of the insecurity and because I suspect that because of the need to impress that a few more friends would be a good thing. I can't see us ever being more than acquaintances/colleagues though.
I can't get over how someone who isn't such a big part of my life winds me up in this way though.

The second person Z is a relation by marriage. I have another thread running in chat which is vaguely related to this.

I want to love Z but there is a massive sense of entitlement there which pushes DH and I away. Z also treats PILS appallingly which infuriates and enrages me.

Any advice as to how I can be more zen about this gratefully received..
Please be gentle, have never posted in R'ships before.

Regarding the colleague: the best way to manage people like this is to find out what makes them tick, and that gives you clues on how to approach them. You can either engineer an opportunity to chat to them and find out for yourself, or if it's appropriate you could try asking another colleague: "Hey, you know X from accounts? Do you find her a bit... prickly? What's the secret to getting her on side?"

Or, if it's someone who's challenging you in your role, you can try direct confrontation. I have someone like that where I work, who kept trying to override my decisions or question what I was doing in my area of expertise, which he didn't really have any knowledge of! It really got on my tits and the fact he kept CCing in a load of other people made it worse. In the end I emailed him privately and just said "I find it really upsetting and disrespectful that you don't respect decisions that I make as part of my job. I was appointed to this role because I have 10 years experience in it. You are a great X and I would never try to second-guess your decisions in that role [even though I didn't really mean this!!]. I hope we can work together with less conflict in future."

Within 5 mins he turned up at my desk and apologised for upsetting me and since then we have had a great working relationship. I learned his strengths and weaknesses (great with organisation and analytics, crap with people) and have adjusted my approach to him accordingly. For example, if I want him to do or agree to something, I will put it in terms of how it will make the business more efficient, rather than how it will benefit an individual.

That is the most recent example but I have been doing this for years in business and it does become second nature after a while. A great manager I knew once said to me "Even if you think you've got nothing in common with someone, there will be. For a start, you're both human and breathe air. Start there and work upwards!"

Regarding your family issue - really too little info to go on, sorry. I try to avoid getting drawn into in-law drama anyway, so can't really comment.

Thanks - that is a good idea re: colleague
Re: relation by marriage: thread here may give you some clues