Look at your parents. They have played a huge role in shaping this dynamic between your eldest sister, youngest sister and you. They have caused this to happen, this goes back years.
What role/s did your sisters and you play (and still do) within your family of origin?. Who was more favoured overall?. Who is still looking for parental approval even now, was such approval always conditional?. You seem to be a giver and they are all takers. I am not surprised at all that neither sister pitched in for the cost of a coffee or any fuel; such selfish people do really act like this and only take, take, take. They feel entitled to act like this because you in their eyes are the family scapegoat.
It is not your fault your sisters are like this, you did not make them this way. Her parents did that.
When siblings are raised in environments where there's conflict, chaos, rejection or a lack of protection, it has an enormous impact on how they end up relating to each-other in adult life.
Psychologically, it all makes sense. Children who share a chaotic, abusive or neglectful home environment may form close attachments to one-another or more often, they can develop an "every man for himself" coping strategy.
Experiencing or witnessing trauma can cause a child to shut down emotionally, and this can distance them from the other children in the family. Instead of feeling connected to their siblings, they can become alienated from one-another.
Parents are supposed to model loving, caring relationships to their children, so if they're mean to each other or hurtful or neglectful toward their kids, the children can adopt these ways of interacting.
There are many reasons for children growing up to become disconnected from their siblings. Dysfunctional parents often overtly favour one child over another, and the siblings are then set up to compete for parental attention. Equally, when parents are withholding of nurturing, siblings often become rivals for the few crumbs of affection they're hoping that their parents might dole out.
Children who grow up in dysfunctional families often feel hurt, rage and frustration toward their parents but most of the time, they're too afraid to express these feelings directly toward Mum or Dad. It's a lot easier to take out their feelings on their siblings, because the stakes are a lot less high, so instead of bonding together out of a painful shared experience, they often end up venting their hurt and anger at each-other.
Sometimes, one sibling wants to be close to the other, but their sister or brother rejects them. It can be out of jealousy - siblings from troubled homes often mistakenly perceive that the other child got "more" of the love, attention and care than they themselves did.
You cannot improve a relationship if the other person is not interested and your eldest sister does not seem at all interested in mending fences.
I would raise your boundaries a lot higher than they currently are and start becoming more unavailable to them all. There is no reason to keep on inviting them to your house if it is not reciprocated.