This is a great topic! I have a tendency to want to make excuses. Like lady tiger, ethnicity used to be the excuse for me…my childhood was drenched in "the government/white people make it hard for everyone". My personal tools for getting past this consist of:

1 - Limit communication with people who shoot you down, make you feel like you can't do things, or distract you from things that should be a priority. Negative people or time wasters are like leeches to productivity. Say NO to them. Just like that. Screen your calls. Move away if necessary.

2 - As other's have said, break down one big goal into miniature chunks. To use myself as an example, if I have the goal of working on a digital painting I can't just say I'll paint when I feel like it, that's setting myself up for failure. The stages of this process consist of sketching, corrections, scan, rough painting, fine details. I'll plan my day/week around it. I wake up at 6:30, eat breakfast and take care of hygiene until about 7:30. Start sketching before 9 am and work until noon with breaks scheduled in between. I find it's helpful to actually set an alarm sometimes. I'll work for 45 minutes then take a 5 minutes break. Besides, if you have set an alarm to do something for 15 minutes you alleviate that feeling like it will never end. It's 15 minutes, surely you can do that? Once you get into the groove, it will be over before you know it. If you have appointments, set reminders in a notebook or on your phone. Do whatever you need to do.

Keep this up and before you know it, you've reached your goal! That is all goals are, sitting down and doing the work.

3 - Research. Instead of comparing yourself to people who have everything you don't, why not learn from them? Nothing is magic, if they can do it so can you. If the people around you aren't helpful, find somebody who knows what they're talking about. OP, you are already doing that if you are on this site. You know you needed help in this area (sticking to goals) so you came here where people may provide insight. Do more of that.

4 - As I said above, I have a tendency to make excuses for myself. "I forgot" "I can't do it" "I didn't get around to it". There are things in life that this just isn't acceptable and there are ways to prevent things from happening.