Should I be jealous?

[Stargazerlassie]

I’ve been with my partner for over a year but have never met one of his closest friends. I have met everyone else including family and I feel secure in our relationship.
The issue is with one of his best friends who he spoils and drops things for and would do the same for her kids (she is a single parent). I think it’s lovely that he cares so much and I don’t usually get jealous and I’m not sure if I should be?
His previous girlfriend ended their relationship partly due to the jealousy created by this friendship and I’ve since found out it caused issues in the relationship before that.
I think this is why I’ve been kept from meeting her.
His family and friends have all met her so it’s not a secret or anything sneaky.
is this something I should be concerned about?

Unless you have incredibly limited time or bandwidth (admittedly Mners do seem to have on balance very little energy to devote to other people), you have space in your life for more than a single relationship. It's not an either/or situation.

Iv had nothing but hell when partners have had “female friends”, plot twist they werent just friends. And i believe very unlikely men and women would just be friends unless one of them is ugly. The woman is capable of it but the man is secretly always down to fuck it she wanted to. Unless she was ugly or dramatically overweight. honestly have a 0 tolerance for it now.

Of course people should make time for friendship in their lives if it is possible.
Again, I don't know who is saying that people shouldn't. It shouldn't be an either/ or situation.
But if you prioritise the friendship over the relationship then of course it's highly likely the relationship will be affected and probably won't last. Because for most people who want a monogamous relationship they expect the relationship to take priority.
That doesn't mean to say you can't have friendships as well. There a tremendous amount of posts on MN regarding friendships of all types so I don't know where you get the impression people on MN don't have friendships and relationships.

What's the issue with previous relationships settling into friendship or warm affection when the relationship didn't have any longevity?
I just don't believe especially in a modern society that people did not have a past. This is a problem for partners in relationships to navigate however there may not be a perfect solution...

There isn’t specifically a problem with it depending on the context.

Provided both parties have no latent feelings and aren’t using the friendship as a mechanism to try and re-establish a relationship that’s fine.

However if one or both parties are using it as a mechanism to be disrespectful to a current relationship, flirtatious or manipulative that’s when it becomes problematic.

As I said earlier if OPs partner is approaching it maturely and openly then that’s fine.

However it’s clearly undermined his previous relationships which begs the question why.

It is evident that there is no consensus on this matter. Jealousy can vary in intensity, and not everyone experiences it the same way. Some may believe that certain types of friendships are inherently flawed.

Both DP and I have experienced friendships where boundaries have been crossed. However, we've been able to address these situations directly and honestly, even when the attention is flattering. We're fortunate to work through these issues by maintaining open communication. This type of issue is one of many couples have to deal with...

Interestingly, the partner of the original poster has kept her a secret. It seems he is not going to give her up.