This is long- be warned.
Bit of background- my mum & dad divorced when I was 6, it was very messy and only recently have they talked like adults to each other and can be in the same room. My dad struggled to "move on", had one long-term girlfriend then split, since then has had a series of intense 2-week style "this is the love of my life" relationships, that then seem to go wrong. He openly longs for a longlasting relationship, and doesn't cope well on his own or seem to enjoy his own company much. He is a musician so lives a unusual life, never anywhere for long & doesn't know many folk where his house is. He is happiest on tour with his buddies, when at home he sinks into depression and is now (finally) receiving some help for "mild" alcoholism.
Since I was 6 throughout childhood we'd see him every sunday, and at uni and after we'd have regular phonecalls always on a sunday. Increasingly he used these to talk about all his probs, often saying that myself & my sister are the only ones he can really talk to. We'd listen patiently, try to be supportive, offer suggestions etc.
I now live with my family in NI, he is still 'based' in Dorset. We see him about 3 times a year- he's always welcome over here and we still speak at length every week (which if I'm honest I sometimes dread). I booked a week to visit family in England, which was just a couple of weeks ago, bringing DCs with me. Timing was organised to ensure both parents weren't working so could see lots of us. But... a week before we flew over dad phoned saying he'd met "THE most special lady" on a dating forum- they'd met up and been inseperable since. My sister and I barely dared to hope this may turn out better than his last few relationships (he has a habit of going out with much younger and often emotionally fragile women) but Dad seemed so happy- and suddenly the phonecalls stopped. Eventually I managed to meet up with them both for a few hours one of the days we were over- he was so besotted with her he barely spoke to us. She seemed lovely and I actually hoped may be better suited to Dad than his exes...
10 days later still nothing from Dad, we assume he's still "loved up" and off the radar (usually we have frequent texts/emails as well as weekly long phonecalls). Suddeny today he calls when I'm out and leaves a message saying "it's all gone to shit". This follows the identical pattern of his last previous "flings" but he is very emotional and gets incredibly down... Personally I do feel his pain, BUT I am also angry that after him going on at me so much that he wants/needs to see more of me and get to know his grandchildren that we were effectively ditched 10 days ago- but now he wants (& expects) to cry on my shoulder. He is not a teenager & I am not his mum. Am I right to feel angry, or should I just let it go and carry on trying to support him?