Op you're welcome.
No it's not ideal they need reminding but we are all imperfect in different ways.
Just as you expect them to step up and fill that gap in their "friendship cv" perhaps you need to make an effort to appear less independent? More vulnerable?
It's something I've struggled with too - to the point I made myself very ill by trying to be "miss perfect"
I had a full psychotic breakdown around 15 years ago, caused at least in part by trying to be the perfect version of all things to all people - mother, daughter, sister, friend, employee, student, advocate, union rep AND my house, daughter and I always in perfect clean and tidy order! Never out of control or late for an appointment none of that.
Utterly Fucking Ridiculous!
But I couldn't see it at the time.
What I also couldn't see was my "little miss capable" act could make people think I didn't need support and even that I'd be offended if it were offered!
But it was a lot like Ross in friends giving it "I'm fiiiine" aye right!
My becoming that ill was a shock to people too and certain people I thought were close friends just vanished...but others that I'd not known too well up to that point were AMAZING and we are close to this day.
At times I've been able to support them too, which they sort of felt bad about at first (as women we're conditioned to feel guilty about pretty much anything!) then I told them that not only was I now able to support them I was grateful to them for helping me reach that stage and I considered it a privilege to be able and welcomed to do so.
I'm more honest now if I'm feeling the well is running dry, I'll say I need a day or however long to recharge, but that I'll be back in touch when I have and that it isn't anything they've done "wrong" and I still love them.
I used to be "miss detached" too, now I tell the people I care about I love them all the time.
The ones who also tended to the similar and weren't very comfortable expressing emotion I've found they started being more comfortable telling me too the more I told them.
One did it the first time "by accident" (end of a phone call I said "love u" and they said same back as a sort of automatic thing) and then worried they had offended me by being too "gushy" or possibly "inappropriate" but once they realised neither was true and that actually I'd felt touched by the comment they started cautiously telling others too and were pleasantly surprised by how people's interactions with them changed.
Dd I was always pure pestering her with hugs and I love yous
because I didn't want her ever doubting it, I haven't the best relationship with my mum.
Occasionally I must admit that was "I love you but for the love of god will you put the milk back in the fridge!" Type thing 
Relationships are hard, we get stuff wrong we say things we shouldn't. But we also don't deserve to be forgotten or ignored by those who are supposed to care about us.