I want to open by complementing you on your sense of responsibility. I know that I'm talking to the right person, because anyone who is concerned enough about midlife issues to be reading about it has to have a well-developed sense of responsibility and concern for their own (and their loved ones') sense of well-being. So, congratulations for taking good care of yourself and those you love.
That having been said . . . let me throw out a word of caution to you: it's very important especially during the midlife transition to avoid the extremes of responsibility. This isn't an idle warning, either, because going to extremes is one of the hallmarks of the dreaded midlife crisis. Now's the time you need to be steering a careful course between Scylla and Charybdis, between the rock and the hard place.
As often happens, both extremes, hyper-responsibility or hyper-irresponsibility, may be opposite sides of the same coin. When you're tempted to let yourself go wild, or especially when you've yield to that temptation, a guilty conscious can drive you to become overly responsible, blaming yourself for the wreckage that you see building up around you. This is a good time for some seriously grounded self-talk.
First, a story. Once upon a time, I had to break some very difficult news to my parents. My brother had asked me not to tell them, but circumstances changed, and it was not only appropriate, it was necessary. So, I told them. As a result, my brother was furious with me, blaming me for hurting them irreparably. Then, it dawned on me: I was responsible for being the bearer of difficult news: that happens. They were responsible for what they did with that news. My responsibility ended with doing the right thing (in this case, the only right thing). I was not responsible for their feelings or their reactions. This was a huge step for me: and a very positive one.
As a person going through midlife (or about to go through midlife), you have a serious responsibility to yourself to maintain your integrity. You have an obligation not only to make the best choices possible, but also to do all the research necessary to make sure that the choices you make are indeed the best choices possible. Denial and self-delusion are common and very powerful pitfalls along the path of growth through midlife.
You are also responsible for making your own mistakes. You can be clear about this: you will make mistakes and some of them may be big ones. Keep in mind that people often learn the most from the mistakes that they make. When you make a mistake (not 'if' you do), you have a triple responsibility: a) to acknowledge your mistake right away (don't try to deny it or cover it up); b) to learn what caused you to make the mistake so that you'll never have to repeat it again; and c) to clean up your mess. You absolutely shouldn't expect anyone else to come along behind you to right your wrongs. That's up to you. What's not your responsibility is other people's reaction to you. In fact, what other people think of you (and how they react to you) is none of your business.
So long as you remain solidly in your integrity, acting with honesty, care and compassion, you have no business getting involved in other adults' business. Did it occur to you that almost everyone in your peer group is also going through a midlife transition? Not everyone will be doing as exceptional a job as you are managing their lives through this difficult period. When you notice some unusual behavior from those in your intimate circle, it may not be because of you; they might be dealing with their own issues. The lesson here is to learn to detach from these people with love. That doesn't mean withdrawing from them (not a good plan if you happen to be married to one of them), it means changing your mind.
When people whom you're close to react inappropriately to you, you have only to remind yourself of three things: 1) you didn't cause it (nobody but you can control the way you feel or the way you behave), 2) you can't control it (the only person in the world whose behavior you can control is you), and 3) you can't cure it (you can neither make another person happy nor fix their unhappiness). These are known as 'The 3 C's'. If you can master holding on to an awareness of these 3 C's, you can learn to do everything spelled out in Rudyard Kipling's famous poem, 'If':
"If you can keep your head when all about you
Are losing theirs and blaming it on you,
If you can trust yourself when all men doubt you,
But make allowance for their doubting too;
"If you can wait and not be tired by waiting,
Or being lied about, don't deal in lies,
Or being hated, don't give way to hating,
And yet don't look too good, nor talk too wise: . . .
You'll have to go look the rest up yourself (it's worth it). In the end, you are responsible: you're responsible for becoming the very best 'you' that you can be. Beyond that, it's nobody's business but their own.