I can never be sure that my experience is all that similar to the experiences of others, but I find it difficult to pray often and with regularity. It's not difficult for any good reason; it's mostly because I am lazy or else for some inexplicable reason, I put it off until it never gets done. Sometimes I manage to keep a nice prayer schedule going for quite a while, but other times it may be a few days before I feel I have really prayed.
We cannot say we are without motivations to pray. We've got a motivation to pray in everything: every good thing we have is from God the Father, for which he deserves our thanks and gratitude; everything we need for life and sustenance must come from him as well, so that we always have need to petition him for our daily bread; we all have struggles and travails and burdens, too, which he tells us to cast upon him (1 Pet 5.7); beyond that, we must always live in gratitude and joy for the salvation that he provided for us -- a salvation that far outweighs any troubles or problems we might confront in this lifetime.
Yet sometimes even recognizing all these things, I find it too easy not to pray! Such is the evil that is inherent in human nature: we can see we have every reason in the world to pray to God, and yet we don't do it.
There is at least this thing, however, which does motivate me to pray. I find that when I pray for other people, my friends or whomever, God answers those prayers in a manner that seems timely. When I pray for friends and family, married and unmarried, petitioning God to work for them in concrete ways that they have need, I see over time that God answers those prayers. I pray for them from the heart, because they're my friends and I want to see them do well, I want to see them flourish. I think that God likes these sorts of prayers and honors them.
Interestingly, prayers for myself don't always go answered as quickly as prayers for other persons. Perhaps the reason here is that I always want things for myself more than for other persons -- I'm not perfect, after all -- and the delay in response is to intended to make me patient. It's a difficult lesson to learn, certainly, especially given our culture of instant gratification. But here we find another great motivation to prayer: it makes us into the sorts of people that God wants us to be. It is like a fire through which vices and shortcomings are purified and removed, and the gold and silver of our true identities as children of God are allowed to shine more brightly, purified of everything unclean.