Hi, my friend. I could have written the exact same thing years ago. I felt like I gave all the time and got nothing in return.
But the reality of it was that I kept getting involved in co-dependent cycles with people. I would rescue them, then I felt used and started resenting it. I would feel guilty for awhile which made me feel more resentful and trapped. Then I would snap and be really mean. Once I was mean to them, I would apologize and become friends with them. Why? Because I made them a victim by hurting them. Once they were a victim, I would set about rescuing them again. I was always miserable and had a love/hate relationship with a ton of very needy friends.
This was also the cycle of my marriage, but I was in the role of your friend. I was always the victim and my ex rescued me. He never let me solve my own problems and became my sole rescuer. That made me dependent on him. He was always afraid I would leave him and he couldn't stand being alone (he was a co-dependent), so he would rescue me. This made me feel helpless. But he would then see himself as a victim of me, i.e. he "always had" to rescue me. Poor him. Then he got resentful and mean. He would flip to a perpetrator and then hurt me. Once I was hurt, guess what? I was a victim again who needed to be rescued.
It sounds like your friend is trying to suck you into a co-dependent triangle. If you google co-dependent triangle or drama triangle, a chart will pull up. It explains how people go round and round the triangle playing the same three roles and everybody being miserable.
The only way to break free of this triangle is to stop the pattern. I had to stop being a victim with my husband, which forced him to stop rescuing me. I had to stop some of the friendships I had with co-dependents. See, it's very hard for a co-dependent person to see they get people into this pattern. My ex still hasn't figured it out. He went from my co-dependent marriage to a second co-dependent marriage and is just as miserable. If I had not put a stop to this merry go round, we would still be doing it over and over.
So it sounds like your friend is perpetually in the victim role. Rescuers are attracted to victims. I'm not saying helping people is bad. But there's a difference between helping people but giving them space to do things themselves and doing things for a person. It sounds like your friend is depending way too much on you for anxiety destressing if you're getting angry with her. She will continue to do it to you though, if you let her. You may need to be the strong one and be the establisher of boundaries.
My mother has been a rescuer her entire life. She complains about how people depend on her all the time and she resents it. She gets angry at them, yet feels guilty if she doesn't rescue them. I've told her to stop rescuing people but it falls on deaf ears. I finally told her that if she isn't willing to change her behavior, she can't expect others to change theirs. She can't understand that the only thing she has control over is her own behavior. We can't change other's behavior. She'll say things like "I would never do that to someone" and then wonders why they don't stop sucking the life out of her. When I ask her why she doesn't stop the cycle, she makes excuses. My guess is that she is afraid that if she doesn't rescue people, they will leave her. I used to feel the same way.
But the truth is that when I left the co-dependents behind, I found true friendships. Equal friendships. There were no rescuers, no victims and no games. It's scary to change these behaviors and it takes a lot of practice to get out of it. It took me about 6 years to finally be able to recognize when I was in a co-dependent triangle and then I had to learn how to break the cycle.
Anyway, sorry, I'm preaching. I'll bet you stop reading 6 paragraphs ago.
Remember to take care of you and do what you need for yourself to be well or to do well in your goals. You're a lot like me in that your heart is so caring for others, that sometimes we forget to put the oxygen on ourselves before giving oxygen to others.