I've been seeing my bf two years. We've had our ups and downs but I've been generally happy in the relationship. We live apart and both have kids.
Prior to the summer holidays he said he will have his kids Friday to Sunday every week (three nights). We usually see each other on a Sunday. We've never introduced kids (his choice), I asked about this recently and it's still a no. So he suggested I come on a Wednesday instead for the duration of the holidays, as I don't have my kids then. Fine. But then he cancelled this Wednesday, with only a vague reason 'not sure what time I'll be home from work/I have to get kids stuff ready'. He's offered no alternative.
I calmly asked about this, whether he wanted an alternative day, but he just said he's busy with work/kids. I asked if he wanted to stop seeing me, as he doesnt seem very motivated to make time for me. He said he is motivated, feels bad to have made me sad.
Still no real progress, it feels like he's fading me out but he says he's not. When I said 'do you want me as a girlfriend' he replied 'do you want to be my girlfriend?' which suggests to me he's not exactly fighting to keep the relationship. He also said 'I don't know why you love me' which he says quite often 
What is the best thing to do now, I'm just confused? I feel like we've known each other long enough not to play games. He's a bit depressed but I'm always kind and supportive. I dont think he's cheating but it's a possibility. There's just a general theme of him not really being motivated to see me.