I think you may have nailed it by citing "jealousy," as her main problem. Prior to you having the new girlfriend, you could prioritize the friendship you made in the hospital. She wishes it could be that way still.

I think we have to be careful about the precedents we set with people, especially people who are very needy. She developed a dependency on you. You were okay with that when you didn't have something better to do. Maybe you felt like you were just helping her get over a hump post-discharge. But her neediness is turning out to be an on-going thing. It could consume more of your life than you can reasonably devote to her. So she is very disappointed because she would have liked things to be as they were when you both first got out of the hospital.

Could it be that she got to kind of thinking of you as her boyfriend? I'm not saying you led her on . . . at least not knowingly, or intentionally. I keep seeing threads in this forum where a supposedly platonic friendship between two people of opposite genders becomes problematic when one of them has a significant other. I think that's bound to happen. Ideally we like to think that it's okay to have cross-gender friends. Practically speaking, though, it tends to not work out without someone feeling slighted. You really have to beware of making a person of opposite gender feel very special, if you don't have a romantic interest in the relationship. From what you say, I hear that she isn't assuming that you were more than "a friend," but her neediness indicates she had come to be somewhat possessive of your attention. The question is: What do you do now?

First of all, I think you have to recognize the role you played in creating this situation. Right now you feel put upon and see yourself as having been wronged. You consider whether she merits your forgiveness. Pardon me, but I think that's a little cold. Maybe you are the person who should be asking her for some forgiveness. You fostered her becoming emotionally dependent on you, but now you are finding that she's become a nuisance. That's exactly what needy people do. It may be that you simply lacked the experience in life to see this coming. That's forgivable. It sounds like you meant well. But this is a valuable learning experience for you, if you are mature enough to let it be that. So I would say: Put aside your resentment and take a gentler stance. I'm in no way saying you should go back to lavishing the time and attention on her that you gave her before. That was a mistake, in the first place . . . but it was a mistake on your part. So put aside the irritation you feel and begin a process of disengaging from this woman that is compassionate and that involves you taking some responsibility. No matter how you do it, she's going to be unhappy. That can't be helped, but you have to do it. But don't be unnecessarily mean about it.

Explain to her that you are sorry she came to depend so much on you. Tell her you wish her well, but that she needs to find other sources of support. Maybe you could invite her to join your new girlfriend and you for coffee, or ice cream, some afternoon. That's not going to appeal very much to her, which is kind of good. It helps her see that she is the one wanting more than normal friendship. You could let her stay in touch, but within limits.

That brings me to my next point. I don't think there really is any good way for a guy to continue in a "friendship" with an emotionally needy young woman who does not have a significant other of her own. If she had a boyfriend, then maybe she and he could socialize with you and your girlfriend. That could be appropriate, and you could all be friends. But she is alone, while you are not. So it's really not going to work out. She needs more from you than you need from her. There is no real reciprocity. Basically, you are going to have to unload this gal. That's what it boils down to, I think. Try to be as courteous about it as you can . . . and learn from the experience.