Promise

When I was young I lied alot and promise people with all kinds of things.
I wanted my dad to buy toys so I ask my brother to ask my dad to buy it and promise to share with him. However when I was in secondary school I realised the importance of honesty and promises. That's why I dun use the word promise anymore.
All I say is I'll try my best. Because now to me if I say I promise and I never do it I'll feel really guilty. I'll never forgive myself. But that doesn't mean I wont say I promise. If I believe I can do it den I will use it.

This doesn't only apply to me. I always hold a rule inside me. If you can't do it den dun promise me. If you promised me den dun break the promise. That's all.
Is that very hard to do that ? Is my request that hard ? I always feel that youngsters nowaday have bad attitudes. So I dun feel I'm a youngster saying that.
Can anyone show me that I'm wrong ? Where's the point in saying sorry if you just gonna do it anyway ?