Well I don't feel the need to write about DD2's mental health history online, but when you almost lose a child to mental health it's extremely difficult. When you walk in on her at 15, unconscious, there is no way to explain that feeling. When you have her crying and crying, throwing up in the bathroom because her anxiety is so bad but she can't explain why which causes her anxiety to build even more.
I've never suffered with actual anxiety (of course we all get normal anxiety from time to time) but seeing my daughter, she can never give a reason, it's not about she's scared of him walking in, but just the thought of the situation makes her so panicked to the point she will be physically sick.
She doesn't live a normal uni life, there are so many systems in place for her (can't knock the uni, have been super helpful). To the people saying she won't book into a hotel, she will. It's sad, but she will. I don't understand the with strangers comment, she will be in her own room, you book in via a computer in reception. She is able to be around people, like I say, I can't explain parts of her anxiety but it's very very real for her.
I don't want to write about when she was 15 and the very personal things around it, but the amount of times she's told me I'm the only thing that's kept her alive to this day, it's difficult to not want to help her in the best way.
This very much will now probably be a "oh poor DD1, clearly coming 2nd because if it upsets DD2 it's not allowed to happen" and no, that isn't true. I've done everything I can to keep both of my girls happy. I like to think I did a good job. DD2 loves coming home and spending time with us. Now she has a boyfriend, she cares less to do so, but I know that's normal and part of growing up.
They both get on well and do talk. DD1 has never understood DD2's problems very well, but they still get on well.
I want to make sure DD1 feels very welcome at home still but of course I don't want to deliberately upset DD2.
Knowing DD2's history and general advice I had from CAMHS and her psychiatrist at the time, shoving things that make her so anxious at her, will not cure her anxiety. The things that actually made her feel that way were tried to be removed from her life. One point she couldn't go to school for 3 months, I was told by the professionals, if that will keep her alive, it's what we have to do for now. I will never forget that. Of course it wasn't the long term solution, but there's a specific way they sort it out, I'm not to sure how but they do do it.
I think the solution is letting DD1's boyfriend stay, but supporting DD2 to go to the hotel.
Thanks for all the helpful replies. Not so thankful for the "she must be 20, but acting 12".