I can certainly see where you would be upset, but it may help to remember that a lot of guys are not that romantic and sensitive and don't realize how important that is to a girl. I don't think it was deliberate really..he just got distracted with his friends..
I could see forgiving if you tell him how you feel, ask him to be more sensitive next time and he agrees and he asks forgiveness if after weighing it out you decide you really love him and the good outweighs the bad by at least 2/3rd (we can rarely get our perfect man). Only you know how deep your feelings run and if you feel you can live with or without him (of course it will hurt to leave but if the baklance is off for you, you need to leave to spare yourself additional pian. If you feel you can get over it and see improvement, you may want to stay.
He was quite qawful to make YOU sleep on the floor and inviting his friends to stay should have been discussed with you and only if ou were cool with it should he then have invited then and they definitely sound like jerks to make you sleep on the floor.
It almost seems like it was planned then showig up, ruining your getaway, and sleeping on the floor to upset you knowing that valentine's day is very special to women. Like they talked this out in advance and picked that day to make you break up cause he was too chicken and is involved with the other girl. I didn't think this at first but after rereading (and those people who answered and didn't read it all were so rude btw) I am starting to think maybe it was deliberate and Hawaiisweetie may be unto sometime.
However, the girl is a problem. I doubt he just met her..it has probably been going on a while. Did you notice any chances in him in the past several months or a cooling of relationship or him being busy a lot? I think that may warrant leaving him..or at least trying to figure out if anything is going on. A lot of men do lie and cheat and if he is, you deserve better. Leave while you are still young and before he hrts you further.
He is very insensitive and if he is going to be a doctor, he will have very little time for you in the future and even after school, so it is really important that you ask yourself if this is the life you want. (should you marry). I was married to a workaholic for 14 years and it was living he__l.
I think you need to ask him to make it up to you by planning something romantic even if it doesn't cost that much and being creative..if you decide to stay and maybe some time apart would be good..
Whatever you do if you want him back don't be clingy..be aloof and do not let him know what you are thinking. If you want him back, maybe do something to trick him into thinking you may be seeing someone else..draw back a little as this is the only thing that may draw him back if he has any feelings.
I did this when I was around your age.after he broke up with me, I went with a cute guy to a party I need he'd be at and was kind of flirty with the guy (poor guy I guess I used him) in my BF who just said he'd like to see others and within a week my ex-husband proposed marriage. (Guess he wanted to seee others but not for me too lol) Unfortunately, I accepted.
Good luck and try to do something fun to get your mind off it and journal. Do good things for yourself. Sometimes when you break up, it is hard but later you see the wisdom in it. I'm sorry your valentine's trip did not go as you hoped. Sometimes those special days don't unfortunately.