I am staying until the end. It is too fun to leave.
'Resto' = RE-sto. 'Divertente' = di-ver-TEN-te.
Use this to commit enthusiastically to the party and signal to others that you are having a wonderful time. It is a generous compliment to the host and creates a festive, fully-committed atmosphere.
'Restare fino alla fine' (to stay until the end) uses 'restare' (to stay/remain). The construction 'troppo + adjective + per + infinitive' = 'too + adjective + to + verb': 'è troppo divertente per andare via' = it is too fun to leave.
Non riesco proprio ad andarmene.
I simply cannot bring myself to leave.
Stronger inability to leave — very flattering for the host
Ogni volta che decido di andare, succede qualcosa di interessante.
Every time I decide to go, something interesting happens.
Describes the magnetic pull of the party
L'ultima volta che ho guardato l'orologio erano le undici. Ora sono le due!
The last time I looked at the clock it was eleven. Now it is two!
Time passing unnoticed — classic sign of a great party
Italian parties that end well before midnight are sometimes described as 'una noia mortale' (deadly boring). The mark of a truly successful Italian party is when nobody wants to leave. The host who succeeds in keeping guests until 3 or 4am is considered a legendary entertainer ('un/una festaiolo/a formidabile').