You shouldn't get discouraged from yoga because you have to use props! That's the reason Guruji invented them! Consider this interpretation of the Yoga Sutra sthira-sukham-asanam (YS, II.46) - Asana should be stable and comfortable. If you reach this through the use of props I think this is absolute o.k. - it is said nowhere that you can only reach a "perfect" pose without the use of props. So work on steadily and for sure you can decrease the use of props (slowly).

Also consider the yamas and niyamas: ahimsa (non-harming), satya (truthfulness) to yourself, aparigha (nongreed) to reach the "perfect" pose. Practice samtosha (contentment) with the pose you can achieve now and through tapas (disciplined practice) you will progress in practice.

Good luck and namaste!