Advice on friendships?

I was meant to be going on holiday with my friend in September but now I'm unsure it's a good idea. Originally my MH team had asked me to just go for a weekend as I've never left the country without my parents and that was many many years ago and she wasn't willing to reduce her length of stay to fly home with me which was stressful and had a go at me when I said I wasn't sure I could handle a flight change and would prefer to go direct. This morning I found out another friend has now agreed to go as her parents were worried about her being there for weeks on her own and I felt very much like they were acting as though I simply didn't want to go rather than the medical decision it was and they knew it had been. I felt quite belittled in the conversation for my struggles as she said I should "just go anyway" despite the fact I could lose where I live and access to the therapy I've been waiting years for if I'm viewed as not complying with treatment because they can't physically stop me. This isn't the first time this has happened either recently with me being shamed for not talking to her when my anxiety has been bad and even when I've been non-verbal, not leaving me alone when I was having a panic attack and she knows I need space to calm down because she was very good with helping me last year when I was struggling. She has also been very hot and cold with me, annoyed if I haven't responded to texts when I've been busy and she's been aware of my plans and my other friends have even started to dislike her for how she's treated me. My parents, having heard what's happened, are now not very keen on me going because they're worried about my safety and mental wellbeing, especially when I'll be so far from home. 

I'm really struggling to decide what to do for the best of everyone involved. I'm not sure two weeks in a different country with two people who I'm not convinced will be considerate and understanding of my needs is a good idea but at the same time I hate cancelling on commitments I've made and letting people down. Everyone else in my life is very concerned about me going with my friend after how she's been acting but at the same time she was so understanding and kind to me last year that I want to believe, despite all that's happened this year, we'll have a good time. additionally, I'm scared of the fallout if I cancel even though she now has company (the other friend going with her) as she can be very passive aggressive and confrontational at times and arguments can be massively triggering for me with my past and she seems to believe that I just don't want to go anymore and not that I'm worried about how I'll cope if that makes sense. I really wanted to go on this holiday with her last year but now with all that's happened I'm truthfully terrified of it as I know I will end up being left out or expected to go along with plans with little consideration for what I need to be okay. 

I'm sorry this was so long and I hope it makes sense, I'm just so lost with what to do and I have such little support available right now beyond my parents and friends as I'm only just getting access to therapy in the next few weeks as I've moved teams and I don't know if I'm being overly sensitive and selfish for not wanting to go because I feel belittled and at times made to feel very inconvenient with my struggles. I haven't really spoken to them yet about how I feel which I know is wrong but I've been so scared of being shouted at (which is a very real possibility as it's happened before) and, maybe naively, I was hoping that everything would calm down with time and things would be better. I'm on the verge of crisis because of all the stress having only just come out of one slightly, which she didn't take seriously either despite the fact I was told to go to A+E doctors were so concerned about my wellbeing. I've only been out of hospital for two years after a decade of being in and out and I don't want to jeopardise the progress I've made on a bad decision, and it hasn't felt like she's been the most understanding of this fact and the severity of my issues even though I'm very considerate around what she needs. 

Do you think I'd actually be okay to go and everything will be alright? Am I just being selfish for being scared I'm going to be forced to do things I'm not fully able to handle and not be supported in favour of their plans? Is it my head overthinking it and overanalysing the situation or my gut telling me that actually she's not the good friend I thought she was and I'm going to be left in a very vulnerable and dangerous situation on my own? Argh. I wish I was just well and never had MH problems so I could go and not worry about my needs so I could fully focus on hers because then everything would be okay :(